PCI 486 Motherboard: The P405
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- เผยแพร่เมื่อ 8 ก.พ. 2024
- This P405 486 motherboard has all the features you want, but the more I worked with it, the more issues I discovered...
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P405 Motherboard on The Retro Web: theretroweb.com/motherboards/... - วิทยาศาสตร์และเทคโนโลยี
The timing of this video couldn't be better. I'm in the process of building my first 486 machine and getting reacquainted with all the terms like write-thru/back, tag memory, and so on. Mine isn't as new so it doesn't have anything integrated, only VLB, no PCI, and no PS/2 header. But learning something new with old computers is always fun
Awesome, looking forward to your video 😊
@@philscomputerlab crap, I was supposed to make a video?
I remember how exciting it was when I got a deal on a S3 based VLB card to replace my Trident ISA video card. I had a 3D billiards game that went from maybe 10fps to silky smooth when I swapped that card.
Also have a vlb mobo without pci and no integrated ide or floppy. Messing with controller cards adds another layer of possible problems. Got a few serial mice so the ps2 port is not that important.
@@PixelPipes 🤦♂DOH!
😂
486 may have seen the largest number of changes within an x86 platform. Early models had just ISA. Next came EISA on the early servers, competing with MCA. Then came VLB. Then came PCI. RAM went from 8-bit 30 pin to 32-bit 72 pin. The first three Socket designs were for 486. It was also the first x86 platform to decouple processor frequency and bus speeds with the DX/2. I/O went from being handled by 3 or 4 ISA cards, to a unified VLB card, to being integrated into the motherboard. The closest more modern equivalent is probably the Pentium 4, which saw multiple sockets and a transition from PCI+AGP to PCIe along with four memory standards.
Ik8
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Pj
They went from 386 class performance in the SX systems to Pentium class performance in the larter 5x86 chips as well. 16mhz to up to 160mhz.
But I would propose perhaps the Pentium Pro platform saw a similar amount of change, because the 'P6' which should have been called the 686 essentially lasted from the Pentium Pro in 1995 to the Core Duo in 2006.
Its crazy to think that all these old 486 boards would be worth so much money now. I would be a millionaire now if only I knew back when I was getting these for free because nobody wanted them.
Yeah I cringe at how much stuff I threw out back in the day, but then that's the only reason the survivors are worth so much now. If everyone saved their old hardware it would still be worthless. The value of pretty much all consumer goods follows a bathtub curve, it starts out expensive when new, then gradually depreciates, then nostalgia combined with rarity causes the value to climb back up.
what do you mean by valuable? I've still got my 486 board, with a cyrix 5x86 running at 120Mhz. Original ram (16Mb) vlb cyrus logic gpu and vlb ide controller. All original from 1996, and all functional lasttime I checked a year ago. So how much would they be worth now. I was about to throw them away as junk. I've also got a rare UK101 6502 based computer from 1979. (I don't like throwing tech away :)
Love how you remind people about having the black wires in the center when installing AT power. The old saying to avoid frying anything is red on red and you are dead. Anyhow another great video love seeing old hardware like this brings back memories.
Collab with Necroware required haha, the guy is a software engineer but is one of the most skilled repairers of motherboards from this era
just a few 10.000 km apart... but no language barrier ;)
I was building a 486 machine last year and I didn't have much luck, I bought 2 motherboard and a complete machine before I landed the proper motherboard I wanted. 1 of the motherboards didn't work and the complete machine I bought is still sitting there untouched, I didn't like the case and anything about it so I'll sell it as is. I built this machine to capture the old memories of playing at my buddy's place. He had a 486 while I had an Amiga 500. We played all kinds of games, most notably:
Alley Cat, Blues Brothers, Cyclones, Earthworm Jim 1 and 2, Prehistoric 2 and Virtuoso. I also have fond memories when he found that he had Qbasic on his machine and he ran Qbasic Gorillas one night and the next they he showed it to me and it was a blast :D
Good on you Phil for cutting down on E-Waste and deciding to work on your repair skills.
You know what doesn't have issues? Phil's Computer Lab
😂 We all have issues
Except hair.exe stopped working 😉
Should note mine is in the process of crashing lol
@@JohnSmith-xq1pz 😂😂😂
@@philscomputerlab 👍
@@JohnSmith-xq1pz 🤣
486.....the memories. Patiently waiting for a video on the Pentium Pro. My favorite computer!
I still have a Pentium Pro in the shed at my mom's place, I should probably drag it home sometime and see if it still works. I built it in an old Gateway 2000 486 tower case that somebody gave me, don't remember where I got the motherboard from. It's a great looking beast of a chip, sadly most of them got scrapped for gold recovery.
@@James1095 I have 11 of them. 2 duals, 9 singles. Always on the lookout for another one.
I never had a 486 back in the days, but I played a lot of Stonekeep, Privateer, and XCOM on a 486 dx2-66 at my friend's house. That was awesome and the main reason for me to annoy the crap out of my parents, until they final bought a Pentium 75 that I could play on all day long. Great memories 😊
Stonekeep! Great game 👍
I drooled over a 486DX2-66 for years, I remember thinking if I had about $10k I could buy a really nice computer with a color printer. My friend's dad finally got a DX2-66 tower with a doublespeed CD-ROM drive and we stayed up all night once playing Under a Killing Moon.
@@James1095 Oooh! UaKM = here's my +1 🙂
@@James1095 I want to play Under a Killing Moon - just received the game in the mail a week ago!
I miss my 486, we got it when I was in high school. I think it was my parent's attempt at keeping me home more and not roaming the streets of good old Quincy Massachusetts. We couldn't afford a DX or DX2 so I ended up with a SX 25MHz, 4Mb RAM and a ~200 Mb hard disk. That was quite the upgrade from the Tandy 8088 with the 10 Mb hard disk.
I still wish I had my old 486 based PC, even with all of the issues and quirks it had.
I think it's important to remember there was a large amount of change that happened during the 486 era. EISA was phased out after failing to gain traction. Local bus on-board graphics happened on a lot of OEM boards. VLB slots came and went. PCI slots appeared after the Pentium launched. RAM went from 30 pin simms to 72 pin. DIN style keyboard connectors started being replaced by PS2 style. CPU clock speeds went from 25MHz to 133 MHz, which was a speed that seemed impossible when the 486 initially launched. I/O like serial, parallel, and IDE went from dedicated cards to integrated on the main board. L2 cache on the main board became common and desperately needed as CPU clocks increased. Graphics went from 16-256 color being standard to 16bit and 24bit 2D being the norm. The dawn of true 3D was beginning. And many more big changes happened.
The Cyrics chips could support PCI, Pentium ?
Never seen these > 100 Mhz DX models ?
Man... The nostalgia of building a 486... Rite of passage indeed! While the first PC I ever built in the mid 90's was an AMD Am5x86 (still technically a 486 of course), today I'd be a bit scared to try to scavenge for parts on eBay for such a build... The prices (and risk) for a good MoBo are just too high... 😰
At the time, my reason to go with a 5x86 was to be able to play X-Wing and Tie Fighter with the best performance possible for my budget (the 1st gen Pentium was just out but was crazy expensive).
For my current early-DOS gaming tasks, I ended up snatching an IBM PS/Valuepoint with an upgraded i486 DX2 for a reasonable price (luckily in surprisingly good condition) last year, which was an easier and safer route than trying to assemble a new machine on my own. It came with a dead CoaSt module (which I'll probably never be able to find a replacement for), but after some RAM, VLB graphics card, and SB16 upgrades, it has become a fantastic machine for my favorite early 90's Sierra and LucasArts adventure games.
With no cache it is a bit too slow for later 90's DOS games, but I have a P233-MMX for those tasks. So, it's all good :)
Anyway, lovely video as always Phil! Have a great weekend!
Nice video as usual Phil! 486 Motherboard is a must have nowdays, excellent compatibility with DOS games. I have Epox 486 with VLB, specifically wanted a VLB (non-PCI) board with CR2032 battery and I couldn't be more happier. I look at listings everyday to have more and more expansion cards.
The best advice I can give you is to practice working on scrap boards before you try fixing something you care about. Remove and replace chips, cut and repair traces, replace capacitors, etc. Practice makes a huge difference in anything really.
As always, extremely interesting. Each time I see one of your videos, I feel terrible for not unboxing back all my personal vintage PCs and making them work again. (Only the pentium works fine, the older ones are sick or possible dead, sadly)
I started learning a bit of electronic fixing few years ago, although with new motherboards which is quite more difficult. There are so many fantastic YT channels of people teaching that I wouldn´t know which one suggest.
My only advice if you start working with the heat gun is to avoid the cheap yellow heat tape to protect plastic parts. I use aluminum tape (for heating ducts, chimneys, etc). Really cheap and amazing.
Also, for these old board with pìn through elements, a desoldering gun is an absolute blessing. They are a tricky and tend to get stuck until you get them right, but the time saving removing slots and stuf is massive, and at least for me are just safer.
The basic diagnosis for the trace repairs in that board, should start with just a multimeter in continuity mode, and see if they actually follow throuh to the PCI slots. I suggest almost needle-thin ending probes for it. If you don´t have those, they are pretty cheap with nice silicon wire in Aliexpress, so no excuse for not getting ones.
Not an expert by any means, just a low level enthusiast, but glad to share. In any case, thanks for your videos, they are always welcome.
In terms of soldering tutorials, I know Louis Rossmann along with community support is assembling PCB-specific repair materials. Most of these are probably modern MacBooks, though I don't specifically know. Rossmann also has livestream workshop archives on his channel. These might be useful in terms of identifying novice mistakes. I remember seeing a decent soldering tutorial on EEVBlog years back. I'll throw in northwestrepair as well. It's also more modern, but the principles haven't really changed since surface-mount took the place of through-hole.
If there is anything more difficult to get working than a 486 motherboard, its a Contaq 3124.
Contaq 3124 is a hybrid 386/486 that will take anything from a 386DX16 to a 486DX50, and has 2 BIOS ROMs and flexible cache options. Always found with a coating of battery acid. I have one myself and can confirm they are way too fun to play with.
My very first pc was Cyrix 486 DX2 66 that my father bought me in Sep 1995. It was a superb gaming machine for an 11 years old kid. I even played Starcraft and Diablo on this machine! Loading was slow but actual gameplay had no issue. Only problem was that the HDD was 850MB which made me to delete games to install another game. I installed Starcraft countless times and that why I still memorize its CD-Key. 😂
From what I remember ALI chipset was to be avoided , I feel your pain , I had similar experience
Love the 486 videos! To me, they feel like the last of the “old” generation where Pentium is the start of the new.
You're right about that. Once we got to PCI slots, platform things began to stick around. AT-size motherboards also largely died off within the late Pentium 1 era.
There's Pre-PCI, PCI/AGP era, and PCI/PCIe; a lot of home-computing growth in the former, rapid speed improvements and competition in the middle, and stagnation once we got to the latter.
Thanks for sharing. I remember upgrading from a 386 board to a 486 and it seemed to be such an improvement.
486 motherboards are always fun to play with, lot of jumper and BIOS settings to get good performance.
Great info vid on 486 build. My 1st and only 486 build had 3 VLB slots. I used a Promise Technology 2300+ VLB IDE card and AMD Am486DX4-120. The performance rocked compared to my previous Intel 386SX at 20MHz! I was running OS/2 Warp 3.0 for apps. I played Blake Stone 3D and the 1st 9 lvls of DOOM 1. I plan to buy another 486 mainboard soon to test compatibility with an operating system I am coding from scratch. Have fun Phil!😊
Also got myself into 486 some weeks ago. Have a IBM Valuepoint running atm and an PCChips VLB motherboard which needs repairs om some legs of the chipset and traces.
That's some odyssey you had to go through... but thanks for taking us with you, it's been interesting to watch, especially as I set up my own 486 (Gigabyte GA-486AM/s with Am5x86, 2x32 MB FPM RAM and 1024KB cache), so I could compare the results. I also used your benchmark suite and ran into some weird issues where when I lowered the L2 cache timings too much, the DOOM benchmark would go wrong (DOOM guy dies and respawns in the middle of the bench, runs against walls etc!). Sadly the socket noses were so brittle that one of them snapped and now I can only use the board lying down horizontally because it can no longer be fastened. You just never know what happens when attempting a 486 build...
love your channel Phil
I don´t find 486 computers to be that complicated if you compare to other even older computers. But at the time we got our first computer ever it was a plain 33mhz 486 with no sound and no CD rom, and like a few megs of ram. back then I knew nothing and then it was hard to understand but I also started my journey with this and made mistakes you can expect from a person never seen a computer before. but I rather quick gathered a lot of knowledge about computers and started building my own from scrap parts. unfortunately I don´t have all the parts from the first computer since it completely died from very bad storage damage after not me btw find it a good idea to wrap it in plastic foil and have it in the basement. But I did keep the working parts from it and still have them. it is a small reminder to me that every story have to start somewhere and that it can lead to great knowledge
Yet another g
reat video Phil. Would love to see a quick video on how you used the T48 to test the cache chips.
Hi Phil, wow nice to know these handy programmers can also be used to test SRAM chips!
Ah! The 486 was my first custom build too! And it was the first overclock: and Intel 486DX2 66MHz pushed to 80MHz by raising the FSB clock to 40MHz. It was quite a jump as the VLBus video card got a boost too. Fond memories 😊
My newest obsession are "SBC"s (single board computer) industrial PCs with a backplane instead of a mainboard. Highly integrated, very expensive, highly reliable and some even utilise the PC104 standard (=Stackable ISA). They come in all flavours from 286 up to core2 - there a even dual CPU Pentium boards. LGR made a video about a 486 SBC
It's a world I'm yet to explore! I have zero experience and parts but just a matter of time 😊
You know what we all really *need is a premade CF/SD card image* for booting MS-DOS- for both old Fat16b/Fat12 2.11/3/3 machines (with XT-ide) and later 6.22 machines. There are plenty of tutorials, but a lot can go wrong!
I would recommend sticking those old cache IC's in anti-static foam (usually pink or black) in stead of normal foam and anti-static bags (usually pink or silver, check for the ESD logo) in stead of regular plastic zip-lock bags just to be safe. Those old IC's can be a bit sensative to static electricity 😉
Yes will repack soon!
Agreed. Note that when I received some dissipative/conductive black foam from an internet purchase, almost half the sheets in the order tested as zero conductivity, so even those should be verified before putting ICs in them.
Of course pink stuff is only for temporary use, and is briefly anti-static (less likely to create static charge), but not dissipative. Carbon-loaded foam is what we want for storage of parts, at a higher cost.
Sort of regret throwing away a 486 board many years ago. I blew the board when attempting to overclock and then hung it on my wall for some time, finally threw it out when moving. But watching these videos, I realize it was a very late 486 board (it had PCI) and that it might’ve been repairable! But that’s a recurring theme: what used to be old junk, is now a treasure.
I'm sure most of us have done something like that. I had a Super Nintendo and Sega CD that both had issues and I threw them out. That was long before I knew about the right people to send stuff like that to for repair. If you have an old game console and it has a problem don't throw it away!
I love how stable the 486 platform was it always just worked.
Amazing video as always!
that platform is one of the best of all time.. cheers.
Awesome video!
It's fun watching you deal with this today.. luckily we have the internet and basically an unlimited amount of data referring to this generation of PCs.. I remember back in the 90s and early 2000s, man.. yes technically the internet was around.. sure.. and there seemed to be information out there but it was NOTHING like how things are today. If you were messing around with a 486 (I was born in 1978 and started my journey in 1985 or 6 with an XT IBM clone) the first pc I built from parts was a 386sx 25. It was pre-internet (to the public at least) and if you didn't have the motherboard book with the motherboard you would have a difficult time figuring out the jumpers you needed to set, knowing what your irq were for certain things you had in your system.. This board is nice it has onboard I/O controller, HDD FDD and all.. that's nice, I don't think my DX4/100 system had that, but it was so long ago now.. I will say I never had a Pentium system.. I went from my 486 to the Athlon XP when that came out.. I had that for a LONG time.. it was a great time to be a pc geek back in the 90s.. Today everything is plug and play and you don't really have to know much at all.. back then?? Oh my.. it was a totally different world.
The "melted/corroded" soldering of chipset pins happened to me twice with two different Voodoo II 3DFx boards within the same pin sections. My guess it might be related to the quality problems with lead free smd soldering of these and potentially high current flow. Then the attempt of "homemade" resoldering might result in the condition you had with your MB and PCI slots. Anyway thanks a lot for another great video. Sitting in the office on Fridays, always can't wait for the evening to open the weekend with the new episode of Retro PC Adventures on this channel 😀
Glad I passed on a 486 Dx100.
I went to a Pentium 75, wanted 100 but I missed out :(
AST FOREVER :p
Hi phil ❤❤ I am from India and regularly watching your videos u are doing a great job
Good memories of the 486. I did dive into this era of PCs recently, and it’s certainly much harder to source quality given the demand in the market. It brought back the amount of configuration and troubleshooting, which miraculously disappeared once you went to Pentium and the MMX range. Plug and Play did wonders to shave off config time and head banging on the desk. However, the 486 was an era when such incredible DOS games were released, and we played with the turbo button on the front of the case 😊. I’m sure I read that a 486 DX4-100 was faster than a Pentium-100 in some benchmark tests…
The MiSTer 486 core does a reasonable job of recreating the 486 experience, as does Dosbian also. However, real hardware rocks those nostalgia chords most!
I think you raise a good point around hardware restoration. We are at a point with what hardware isn’t in a landfill, the skills to repair are not common place. It would be excellent if you could take us on this journey Phil as I know I’m keen to learn more 👍🏻
I didn't know you weren't already handy with electronics repair. I guess I'm spoiled by channels like Adrian's Digital Basement where he tests out everything before swapping components.
Me I wouldn't know a cache memory chip from a floppy controller, and the number of times I've picked up a soldering iron and the number of times I've burned myself with it both remain at 1.
I would not want one of these today lol. The hardware has been doctored by this time in life. Finding a board from that time that has zero issues would be like watching Cruise do another mission impossible. Good video liked the in depth review.
I have built three 486 machines....and modded an Early Pentium board to run a K6-III 575mhz....I function in disfunction, I must be a genus heh...I can say this much my M919 with a one meg cache just flies.
I've thought about it sure, but...
the internet would realistically be the best option to find hardware in my town
I've only ever built one computer before. My Ryzen 3 1300x "All in One" Retro Gaming machine (I call it all in one becouse it was built to play DOS/Win3x,9x, and XP/7 era games)
I've got everything I need setup on DosBox
The thing I love about the 386, 486 and Socket 7 corridor is how much choice you've got for what to put in it, especially CPU-wise. Still looking for a PCI 486 board for the cost and flexibility reasons you mentioned. From my own recent adventures, I've been amused about how what would have been budget boards back then tend to be the safer bets now, since tighter integration means less can go wrong.
I had a 486 DX2 66MHz iirc, and after that a 486 DX4 with 100MHz. Can't remember the details, as I was very young and my brother's did all the work setting these up.
I'm currently in the process of reviving my first PC, a Commodore PC10-III (Intel 8088, XT machine). I did find the videos of Adrian's Digital Basement very useful for repairing the battery damage and the first debugging steps with my oscilloscope (checking the RTC chip, address lines, ...). Still have a lot of work to do, it's not working 100% yet.
Greetings from Germany :-)
Happy Friday Phil!
Thank you 😊
I felt the same way, I never used to deal with soldering and circuit board repairs. But when you deal with old hardware and collect it, you inevitably have to deal with it. I also have an Asus motherboard with 486DX 4 100 MHz and 128 MB RAM. I even used the board with a GeForce 2 MX. But it is very slow and you cannot install DirectX 8 or higher. Already tried it. Now I have a 3dfx Voodoo Rush in the 486. 😂
I had a 386 system, my first PC, but my first build was a socket 7. I never got to check out 486 systems.
very relevant video to me; going thru much of this same thing as i build a new 486 machine. one board keeps corrupting its memory, no matter what BIOS settings or modules i use. another board has a non-working turbo header. another board has non-working secondary IDE connector. i've built 486 machines in this past, but it seems to be quite a struggle this time.
I would like to see you investigating and fixing issues on old motherboards, I am confident you will solve any issue there, 😏
I own it, it's an interesting motherboard, it enables the PS2 mouse interface by installing the missing EXT KBC and 74 chip, then disabling the INT KBC via a jumper.
A lot of those QFP chips will either tear pads or de-laminate themselves over time as the board flexes, thermal cycles, etc. Some of them were just plain soldered poorly. Considering the repairs done, it stands to reason that there are likely more unstable or broken connections.
Very good video Phil!!!
I still have the infamous PCChips M919 VER 3.3B/F, aka the 80486VIP Green card, with all the majestic QFP fake cache chips!!!!
The real cache, is a propietary module stick, very hard to find. A Cyrix 486Dx2 50Mhz and then, the marvellous AMD Am5x86 133Mhz were my CPUs for years.
Always had being amazed by the Icons and mouse support by the AMIbios.
G'day Phil,
Sometimes it can't just be fun & games as there is always something new to learn or relearn if we have forgotten, just like your progress creating this video 😁.
Hope you have a great weekend, I'll be using my Victa Controller to play Lawn Mowing Simulator as I have a House Inspection next week, it's so realistic 😂.
All the best!
Great to see Phil doing Max Payne's expression for the thumbnail :P
great video bud. only of the best machines i had was a 486DX4 100 with VLB. it was amazing. i DOWN graded to a pentium 60 yes the old 5v POS and regretted it badly even till 2024, all the while i had my amigas and the like. i loved my DX4100. after watching a vid just recently where a dude built almost the same config i will do it again. best machine EVER. thanks buddy
You and me both! My very first custom built PC was an AMD 486 100 MHz with VLB. I loved that PC. All the parts arrived by mail and I was so excited. My next machine was a Pentium 133 which was a huge upgrade, but still, that 486 I have fond memories.
You are definately right about it being a rite of passage! My Peacock 486 has a UMC Motherboard (also chipset) and I have to say it works flawlessy. BUT I completely forgot that because its an early implentation of PCI it needed to be IRQ-assigned manually in the Bios! I was stuck for days and days trying to get it to properly detect a ethernet card and a voodoo card! so frustrating lol
I jumped on a 386 and 486 platform recently just to get the experience. Let's just say it is not as easy as i thought. A lot of weird anomalies. Still a nice hobby tinkering with them. Had lock ups on the 486 at first but a cooler sorted that out. Now it's the isa slot messing up with video at times. Can't get the cd rom to work beside the hdd also. Even with 2 separate controller cards. Cf cards work well at least. Got the system all set up without the cd rom just using floppies and running win 3.1. Nice to see videos of you also messing around with those older platforms.
If I was to buy a working (or easily repairable with PCI) dedicated 486 board, I'd be looking for one with VESA local bus, as I have a Trident VGA card that visually appears to be in OK condition - apart from not having an I/O shield. And my only 486 board (ISA only) has a soldered SLC and needs the level of corrosion repair that I simply do not have the skills to fix (It was clocked lower than my 386 as well).
I really did receive an eclectic range of retro PC parts 9 years ago.
Can't wait to watch you repairing boards and misc parts. Micro soldering is not hard. It's time consuming.
No doubt your aware of the many great board repairers like necroware, vswitchzero and Tony359, Bits und Bolts, just to name a couple.
The additional tools they use, which you might be interested in, are a Dremel with a soft tip, to carefully remove the solder mask when they repair tracks and need to create bodge wires and board heaters so that the solder melts more quickly when the iron is placed on the tracks pad, preventing the lifting of tracks from overheating.
I'm sure they would help if asked, if you run in to a difficult problem.
Yea I watch all of them 😊
i have a PCI test card - it tests the contacts in the socket - same as the post card around $10 but green pcb with battery on the back and many little red LEDS for each pin - push it in and press the button - no led = problem contact . and check the pin solders on back of board - ive seen the pins bet and solder joints cracked , easy to reflow with a bit of flux - also suggest use ur microscope and ur multimeter in beep mode (diode) and scrape a bit of those traces back with the repairs using a scapel or sharp tweezers - make sure u have continuity and no bridges between those repaired traces- they could cause interference from the chip
I’m trying to find one of these cards on eBay but can only find post cards. Is there a specific term I can search for?
@@zuldanfpv4634 looks like ur right i didnt realise they stopped selling them- i got mine about 5 years ago - only PCIE slot testers now
I have a similar board: GA-5486AL. Had to repair it: leaked battery destroyed a number of traces and vias and ruined bios chip socket. Also had to replace south bridge (found replacement on Ali) due to damaged and missing legs (some pads ripped of as well). Config:
GA-5486AL (512К caсhe)
AM5X86-P75 (AMD-X5-133ADW)
64Mb EDO (4 x 16, that's all mobo can handle)
Alliance AT3D (4Mb of replaced memory)
EvilKing 3dfx VooDoo
Realtek 8029 (with bootrom customisation)
Creative AWE64 (0.5Mb chip replaced with 2Mb)
Sintechi SD to IDE adapter
LG 52x IDE cd-rom
PC-dos with lan support
Have an interesting super-socket 7 pc as well.
i kinda love this PCI 486s, they are sooooo flaky, but they do feel more "bare metal" than newer platforms. but they are quite reliable once you get them running properly though, i can vouch for my SIS 496/497 board.
I had some PCChips M918, it like randomly crashed at times in DOS, and Win95 was a no go on it. I replaced it with a VLB board with a Cirrus Logic VLB card and that one seemed more stable and Win95 actually worked on that. I did use the ram, CPU, and cache from that board
While I did have a mate whose brother had a 486DX2-66 and it was really my first experience with DOS gaming, I have to say that I am more nostalgic towards the Pentium 1 as a Pentium 100 MHz was my first IBM compatible. However, I have now managed to get a 486DX2-66 motherboard but I just lack a case to put it in. I am actually considering doing a Woodgrain 486 since LGR's videos about his escapades with that machine have inspired me (and many others I have learned over the years) to make such a machine. This motherboard has VLB and no I/O built in so I will need cards for everything. Ultimate goal will be to find a 3DO Blaster for it and a Creative 563-B CD-ROM drive but those are super hard to find at a reasonable price. But it is good to have goals, isn't it? :)
3DO Blaster, nice!!! I've never even seen one!
Not the topic, but can you please make video explaining how cache works? I recently assembled 2 486 PCs, one Intel 486DX4-100 and one DX2-66, I had the joy to discover all the problems (5V CPUs, 3.3V CPUs, FAT16 vs FAT32 needing Win95 OSR2, problems with jumpers not documented, problems because most of the HDDs are LBA and not CHS needing Ontrack Disk Manager from your website). But I NEVER understood what cache is, how to select the chips, and to set the jumpers. For me it is like RAM on a 486, you try a chip, it is either working or not but you have no clue until you try. And from your videos, cache seems to be quite important. But anyway, thanks for your videos!
This takes me back. The scourge of fake cache chips, setting CPU core voltage with jumpers that could get knocked off and fry your CPU, juggling IRQ, DMA and address settings for ISA cards, and my "favorite" issue was not quite compatible parts that sometimes just refused to play together despite the fact that they should. I had a 386 motherboard that my Soundblaster Pro just never worked right in, all .wav sounds had a weird screech after them. In another case I had a 386sx that worked perfectly with the original 40MB IDE hard drive but with any other drive it would hard lock as soon as any executable was launched. Then there was the insane cost of RAM, it was SO exciting the first time I had a machine with a whopping 8 megabytes. Good times, we're so spoiled today.
Für den Start in die Hardwarereparatur kann ich nur die Video von Adrian's Digital Basement empfehlen. Die Videos sind zwar manchmal langatmig, aber sehr detailliert und am Ende hat man das Gefühl wirklich was gelernt zu haben. Der Weg zur Perfektion ist sicher sehr lang aber den ersten Schritt zu wagen ist das Wichtigste. Für mich bedeutet das, daß mein C64'er vielleicht bald, nach fast 30 Jahren, wieder läuft. :)
Gruß aus Norwegen nach Australien.
Vielen Dank!
Man! Played Mortal Kombat 1 in my 486 back in the day! with Sound Blaster 16! \m/
What's sneaky about barrel Batterie repairs/replacements? Regarding 486 I run into a lot of issues with these boards overall. I'm now running a Pentium 1 motherboard with intel chipset and intel Pentium 100. Absolute hassle-free and very happy with this decision. It also features two usb 1.1 connectors for easy file transfer and modern interface devices.
Yes Pentium systems are much easier to work with...
Friday morning breakfast with Phil's. Steak and Eggs from a microwave...love it.
Looks like address bit 28 on that missing pin. Might be working as long as you don't need to address a device with that address bit
It's amazing how many vendors sold compatible CPU's for a single platform. Nowadays it seems surreal 😅!
Thanks for the video Phil 👍!
The 486 motherboards i still have a few, for testing i use a POST card ,it can fit ISA slots as well as PCI , some motherboards can have issues with the RAM memory ,some prefer Fast page or EDO, i have a board with fake cache ,just blocks of plastic :}
Hallo Phil, got inspiration from Bits und Bolts ? 😆 great video as always
😊
haha i love your need for speed porsche t-shirt ;)
That is killer!
ive never had a 486 pc, my first computer was a windows 95 but id love to build one soon. currently working on a slot 1 build.
Which hex editor do you use? I recently revived a voodoo 3. I dumped the og bios, flashed it with a newer version but it failed, so I flashed the original bios I dumped and it worked? Im not complaining, got a working voodoo 3 but I wanted to look at it with a hex editor. Thank you for the awesome content as always. Makes my day to watch these.
To find the root cause of random death is one of the most dificult and time consuming task. One strategy would be to list the potential areas for check and do it step by step. First I recommend the thermal check with IR camera. Maybe the CPU or/and other chips needs more cooling. Try to get the datasheet of the hottest chips and check the working temperature range. Try to reach a cooling solution for the quetionable chips in the midle of the working temp range. After the improvement of the cooling try to make a video on the test including the IR camera picture as well. If the crash is not colerated with the temperature of the critical component at the moment of the crash than probably you can close out the thermal causality of the crash. Move on to the next area to investigate.
I would select the power supply area next. You need oscilloscope to quickly measure voltage and indirectly current values of the power railes. Make a video about the test including the scope display. With this setup you can determine wether correlation exists between the crash and the measured value. It could be a voltage drop or an amperage spike at the time of the crash. Worth to check the total power consumption vs the rating of the power supply. Select a powe supply with 50% more rated power at least than the max power consumption during a stress test of the board. If it seem s to be OK than move on the next area. There are plenty of them to investigate. Good luck!
Very nice. Hopefully some day someone will figure out how to make open source 486 motherboards and a fpga chipset that doesn't have the same limitations as vintage chipsets.
If you suspect capacitors, my favourite tool is LCR T4, and it's very cheap. There are very similar ones with a shell, perhaps you want to choose one of those, nor sure they're called T7 or something. You need to lift a capacitor though, at least one leg, or take it out completely. I don't particularly like using multimeters or LCR tools that can be used in-circuit, the telling power of the results is VERY hit or miss, especially if you're lacking EE background. But also i don't feel like this board should need capacitor work, like they're barely doing anything here.
I would really pay a little extra attention to the visual state of the board. The solder just looks a little unconvincing everywhere in colour and texture, and there is corrosion on the spring of the coin cell socket and on the retention springs of the memory sockets, which suggests it has been stored wet, scratches and repairs around north bridge suggest it got piled on and banged around. One of the pins in the top PCI slot looks uneven. There might be pin damage or corrosion, maybe needs a clean and deox, and check all IC pins with tweezers that they seem stable. One of the vias at 6:30 is missing its fill. It's best to check that whole area for continuity and lack of shorts. The repaired area around pin 70 is RAS pins for RAM, not PCI, the signal integrity here is critical, and the via could be cracked inside, being intermittent. The repair around pin 75 are for IDE bus, which in that era doesn't have CRC measures to detect and correct transmission errors. I suggest the system needs dedicated software tests, namely memory test, and IDE error test of some kind. If one of the two errors out after a while, you'll know to leave the other area alone.
Lacking experience, you probably also want to practice on something that isn't a valuable mainboard for your soldering technique. Some sort of landfill electronics, routers often get thrown away, or disposable soldering or microcontroller kits. Materials like wick, solder, flux, are more critical in quality than the capabilities of your tools, though good reliable temperature control on soldering iron and quality tips are quite desirable.
I should say though i don't at all hate this board, in spite of the thumb down in the thumbnail. But my interest for 486 is overall very limited, i like slightly newer systems. Though if i did find my very first board or one of them, which were pci 486, if i could even remember what they were, that would be nice!
My take on 486:
Great nostalgia but not so great to work with: most don't have PCI or built-in IO, and use VLB which has its own kind of quirkiness.
Regarding repairs: NecroWare got me into repairing old motherboards and cards. Can also recommend Bits und Bolts.
I picked up one of these boards during the pandemic, reputable seller who wanted to sell it preconfigured with an AMD 486 in it to make it easier. But I had recently rescued an Intel DX4 from a gold scrap merchant so I wanted to try that. Put it all together and very very clumsily for me I don't think I had it mounted right in the case. I did a bit of ATX to AT bodging to get stand offs right. Something on the rear of the board touched the case and it was bang and seemingly game over on first power on. It may be rescuable but I haven't had time since to try again. :-(
0:12 That a bit scared me xD
I think It would leave my potential 486 PC as Vanilla as it could be. I wouldn't play around with those L2 chips and such, since at the moment I don't think I could have patience to deal with those issues like in this video. And just hoping that it will be enough for what I could have on it, and perhaps leaving that for later at least.
486 needless to say is still an interesting platform, despite not being perfect, issues it can cause and being flexible but with extra steps to take. 386 and older are cool and all, but with those I feel like I could be wasting their potential, at least that's what I feel about them right now.
Ah, this is the last of the AT mobo's because they sport an PCI slot. The next gen mobos start sporting ATX though there are a few AT mobos which has an AGP slot.
nice video Phill I have the same issue whit an identical board plus my sms io chip is not working I will try a bios flash
I had a 486 my rhist build i nead to cheke the loft... saying that excelente vídeo
I love WinBIOS!
I hear you! 😅 It’s a full year I’m trying to get a stable 486 VLB build and after 2 boards, 2 vlb vgas and many hours spent I’m not getting the cdrom to work 😢 I’m going for an ISA multi i/o controller instead of the vlb one I’m using 🤞🏼
Yea with DOS at least you won't notice the difference. Use something flash based. Under windows 95 maybe but that runs like a dog on a 486 anyway.
the SiS 496/497 chipset seems the more solid of the PCI 486 chipsets in my experience, i had no lockups or reboots or hangs, even Windows 95 ran fine on it
Learn Electronics Repair channel is great for learning he has videos for beginners.
Thanks for that!
Also good skills can pick up from Necroware channel. He is doing only retro pc stuffs.
I found the PCI boards to be more stubborn to work with versus the VLB variants. This is probably due to the early adaptation of the PCI chipsets. I had to fight with my ZIDA 4DPS for a few days in order to make it stable. Now it's running a patched BIOS from 1998 on a Flash ROM that I had to sacrifice a P5A-B for. I'll eventually get a Flash ROM for the P5A-B and get it up and running again with a Flash ROM programmer. Currently the 4DPS is paired with an Am5x86-P75 with an MGA Millenium 2MB. Primary game is Raptor, which I missed the most.
Fun that I found this exact board, with two weeks older ALI M1489 - which is important here because just two months younger than yours has the newer stepping of this ALI chipset which makes it significantly slower at PCI VGA transfers. Which is still on the faster side for a PCI 486 yet the SC variant is better. Just try it with something like a Riva 128 or a Tseng ET6000, or perhaps a Matrox Mystique and you'll see it scream.
On stability issues - it's a valid option to try different memory modules or even type as this board should work with EDO RAM, at least mine does and with the right BIOS it might even be faster with it. And not equally stable with various sticks.... Of course the same is true for the cache chips, they can be unstable at like 40MHz with the tightest timings. And I found it VERY difficult to find any cache that can do 50MHz at 2-1-1-1 timings. Thankfully I usually use this kind of board to host Am5x86 chips at 160MHz - so 40MHz is the max FSB I need.
Happy PhilDay Viewers