Nice video, thank you very much. May be as an idea, I saw some similar videos from Russian guys and they all told, that if on of the MOSFETs blew up, it is usually not sufficient just to replace it. In the best case it will work for another week or so and, in the worst, like in yours, it will blow up immediately again. They say, that if you have to replace a MOSFET, you always also have to replace the controller, because it usually is the reason, why the MOSFETs blew up in the first place anyway.
I think you're right. This video ended up being super popular, so I might take another swing at this, just to see if we can finish the job. It'll be a while though!
@@Adamant_IT Yes, i also believe the controller has turned on both mosfets (high and low ) at the same time, creating a path to ground through the low side mosfet probably, blowing the high side one. Replacing the controller too, might solve the issue
@@yosuhara No - its the mosfet driver chip Adam mentions: NCP 81062 from ON electronics. They are available from Aliexpress.com Links to the ON datasheets site: www.onsemi.com/ www.onsemi.com/pub/Collateral/NCP81062-D.PDF www.onsemi.com/pub/Collateral/NCP81174-D.PDF Apparently the mosfet driver chip fails by turning on the lo-side mosfet simultaneously with the hiside mosfet, thus taking out the weaker of the 2.
YOU ARE REALLY AMAZING. MY REGRET IS WHY I DIDNT FIND YOUR CHANNEL EARLIER! A GOOD CRAFTSMAN ALWAYS SHOW HIS MISTAKES SO WE ALL DONT MAKE THEM! YOU ARE EXCELLENT EXAMPLE! REALLY LIKE YOUR TROUBLESHOOTING CYCLES!
I always watching your videos, and thank you that u mentioning the degree Celsius of hot air. Make more videos where here and waiting and starting learning
thank god for these videos. I have a evga 960 that had a similar meltdown, Inductors exploded and it shorted, and the fan bearing blew out. the blue pcb burnt to a brown color. hoping it didnt destroy the traces in the pcb, that will make this repair a thousand times harder... But i wanted to try and practise repairing components. And this video was exactly what i needed! thanks a bunch!
Lol i did the same thing you did too! I plugged the 960 into a lower wattage psu, a 550 and it took power and fan kicked on, just didnt produce an image.. so i tossed it into my system to be faster with troubleshooting and plugged it into a 850w and suddenly i smell a burning smell, the fan is twitching and came to the conclusion my 850w surged into the card and fried a bunch of stuff.
In my experience (not specifically related to graphics cards), if your MOSFETs short, you should assume the drivers have been damaged and replace them as well.
That was really entertaining. Shame it didn't turn out as you hoped but hey, after all the replacement surgeries and explosions you still got it to work. That's a big win in my books. Keep it up! :D
Thank You. And yes, learned alot (and I was sure I knew everything🙄). I enjoyed the magnum length video version. I ordered a pizza and told my GF to get lost. OK, I didn't do that.. I just let the air out of her 🤤 Anyhoot, you fought the good fight. Think I will pickup one of these classics. It will feel like an old trusted friend. Cheers 🇺🇸😁🇬🇧
id love to see you fix some rx 570s an 580s i have a bunch i could send u man, i need fixed, but to see u do it would help me fix mine i love how u go over everything an explain it, SO AWESOME MAN i love you!!
Interesting look into buck regulators. The only thing you didn't try was swapping out the driver i.c. I think that was faulty (thermally unstable) and provided the path to ground for the high side f.e.t. The driver i.c. probably switched the f.e.t. on for too long, killing it.
I like your videos very much. Your speach is 98% understandable for a non native, non supreme speaker :) You can teach me electronics - in English! - That is way more rare than you may think...
I love the cheap compact testers/o-scopes. However in this case I'd love to see a decent analog scope, at least in an educational video. Just constructive criticism. Nicely done though.
True that, he's getting confused a lot just because the scope is limited and doesn't show properly what's going on. I think he should see full 12V on the mosfet output, mosfet is either off - 0V or on - 12V, it should not show anything in between.
@@Arek_R. That's not actually true, with such high switching frequency you can't constantly hold 12V or 0V at the output, I will always be something between. And for such purposes there will be no difference between cheap and professional o-scope, only slighly change in readings accuracy. Personally I use ad1102ca from Atten which isn't either cheap or expensive, but didn't notice difference when compared to cheap ones or some high end for thousands of $ ;)
I watch your videos like i watched The Shawshank Redemption or other great movies :))Imagine in high school i was the electronic class and none of those teacher talked like that and was so boring.Now...i watch with big curiosity, you explanation are so good and i understand no matter if my english is bad. :)) GOOD JOB!
Great demonstration of how buck regulators work in real life. 👍👍👍 After theoretical explanation in a couple of previous videos it's nice to actually see it "in action". 😊😉 Thx for the effort.
Please use Flux and see the magic how your soldering will be ! For soldering and desoldering use Flux please ! Very good informative videos I am so thankful to you for your effort and work! Best regards,
Still, a great vid. I had no luck trying to replace a broken off 3.0 USB header pin on an older ASUS mobo, by desoldering/soldering (plan was to us a leg from a LED) but still felt satisfied with my effort in trying.
I'm a retired electronic tech from the USAF and I've seen a capacitor test good but then go short. Replacing the capacitor corrected the issue of a system blowing a fuse. I'd say replace the Q1 cap even if it tests good.
Watching ur vids and I really love the learnings I've been picking up. I got a gtx 1060 3gb faulty.. No visible defective part but I am not certain ofcrs. I wonder if u can make a troubleshooting video how to identify shorts opens and defective part esp the critical parts. I would and I guess most of us ur followers will really appreciate that 😊 🙏🙏🙏
Hi I am loving your videos on repairs keep them coming. How ever it is not really a VRM, that term was used when the voltage regulator was on a small pluggable module, hence Voltage Regulator Module. I am guessing the the topside FET is not switching properly maybe the bootstrap capacitor or driver IC is not working properly. The input inductors are only for EMI reduction, if they were not fitted and it went short all that would happen is the PSU would go into chirp mode assuming you do not have any other components in the board that would fail 1st. I believe the weird chirping you saw on the scope was a sign it was not switching correctly, and the waveform on the output of the FET will be a pulsed one from GND the 12V, I am assuming your pocket scope cannot display the correct waveform.
I find it funny that right after I left the video and commented you need to read schematics, you start looking at schematics. Albeit not the card manufacturer schematics. I wonder why? Also critical because the phase ground didn't end there, couldn't you have traced it farther? I do understand though you showed how you can figure out without schematics what goes where, which is handy if it is obscure or old, but that card wasn't either. Can't you get small business loans to cover ultrasonic cleaners and Schematics websites? I can't find them for free but idk. Thanks, this was awesome! I learned a ton. Entertaining as well.
Forget your Kyles, Jayzs and Linusus.... This real IT problem solving! I wouldnt attempt it myself though... My clumsy fat fingers wouldnt be able to be this precise
Sir, it's 3:48am in the morning... WTHECK just happened.. all I heard was turbo dead.. Mosfett just dropped dead!! 😂R.I.Pieces Mr. Mosfet. Sorry sir, I was quite happy for your accomplishment. Use the donor card.. what else can work as an inductor replacement? Dr. Frankenstein we need an Abby Normal Brain.. A better Mosfet that can handle a fuller load. This way the resistors can still take care of some of the flow.
These two pcb's are absolutely identical, I bet down to even a single wire and its physical pos. on the pcb, so it is highly unlikely that that you couldn't take any individual part and exchange it between the two pcb's - with only one exception - if the two boards has significantly different timing specs. Just about all semiconductor manufactorers have don those designs since the mid 60's and Intel, AMD, Realtek and yes Nvidia and ATI too - you get a complete design with schematic diagrams, BOM and most often even Gerber and drill file. I once had a collection of 8 different MB's that original was a Intel BX-440 - only difference was the color of the solder mask, occasional different color of a connectors plastic (never the position) and the top silk screen that stated the name of the OEM - as I remember ASUS, MSI and First apart from Intel, I can't remember the last four :-) They were carbon copies of each other - except from major build quality variations ;-)
If you have time a nice video would be one where you show how to test each item and what it should look like if it is good. I have several bad video card that I purchased trying to learn. I took a power supply and put 5 volts and 1 amp into the back video card 6 pin plug and tried to follow where the voltage stopped. I jumped the mosfet gates with 5 volts to try to get the mosfet to turn on, and in spots it did. Ground on one side of caps but got no futher. A video starting at the 6 pin and checking each item saying what you should see and what you did see moving along would be great. You know what things should read and jump right along, but a video for more or less beginners step by step would help alot of people I am sure. Thanks for your time and videos.
"the short magically disappeard" :D There's no magic, the problem lays in the method you use to solder the mosfets (or actually any QFN-type components with thermal pads), placing to much solder on pads and then trying to push it out is a bad idea, 'cause you push it in all 4 directions, 3 visible and also the one that goes to G and S pads of the mosfets which you can't see but for sure will make a short circuit ;) So in my opinion it's better to clean the pads from old solder and use solder paste (even some cheap chineese one), SnPb is preffered (by me) 'cause of lower melting temperature :) @1:09:40 you start thinking why it shorted again and burn upper mosfet while it has no connection to GND, it's all caused by failed PWM controller and/or driver which drives low side mosfets constantly so at output you have GND all the time and when swiching upper one it simply burns out ( double lower side mosfets can handle that short, single upper one will blow up)
at the start of page 13 of the datasheet at 21:57 sec, it's clearly written "if a phase is unused, the differential inputs to that phase's current sense amplifier must be shorted together and connected to the output"
It's hard to imagine it's worth your time to attempt to repair a 960 board. I don't know about the U.K. but a board like this is worth about $150 functioning, it seems like too much time and effort for not enough potential reward. Anyway, I really enjoy your videos, keep them coming!
cleaning with isopropyl alcohol will help a lot and I believe that part that you did not know what it did is some kind of a boos or buck converter for voltage depending on the configuration.
Did anyone else notice that one small black component, likely resistor, moved off one pad when you first removed the shorted MOSFET in previous video? Then solder wick ate that half loose component while you cleaned pads of the shorted MOSFET. Would be interesting to know whether that missing resistor next to the blowing MOSFET affects something there and could cause the blow-up instead of damaged driver chip. I've actually found one Matrox Parhelia in scrap pile that smoked MOSFET of one GPU power phase shortly after it booted with good picture. Likely the reason was that one small component got misplaced on the rear side in that phase when the card got under many heavy devices deep in scrap pile.
Your efforts are really interesting and full of knowledge. I have got sufficient knowledge of lap tops. Can you share me the use of schematics of lap tops.
i got a gtx970 that set on fire, i had it water-cooled but the pump died. there are a couple of scorch marks on the water block it looks like a couple of tiny diodes. i might have to give this a go at some point.
I just works on same reference board with exactly a same issue (except mine go nuclear around inductors so it need some PCB etching and I end up replacing them with fuse as only three spots for inductors survive blast) and yes, I end up replacing control IC because first mosfet blow up few minutes after replacing. Now it work ok. Probably original problem was IC and not mosfet same like in your case.
Question is.. have you tested the coils which the mosfets are working together with? If they all have the same characteristics to different frequencies, or if other components have measured values slightly off specs. It's a longshot, but it might be the cause of why it's the first mosfet that shorts, if the harmonics might be off tune causing standing waves, or if some other component interferes. I was thinking, maybe you could trick it into running 2 phases instead of one at lower and moderate load to smoothen the transition to 3 (or 4) phases? I really enjoy your videos and your waffling :)
I know this video is getting on a bit now but I just stumbled across it, and I couldn't help but notice that the electrolytic cap by the auxiliary power connector seems to have the polarity the other way round, just a thought...
love your videos adam but need to say tht the elastic tow rope example is verry wrong.an elastic rope would infact ad super speed to the car being towed and infact cause it to smash into the truck towing it.the toe rope needs to be solid so there is no force in towing.ive pulled hundereds of cars and just sayin.wrong example.that being said i have truely learned alot from you and your videos.bravo and keep it up your a great teacher..Robert Whalen.Ontario Canada
Man, i am not an expert, i do repair things from time to time, but your voice and especially your English accent, really make me watch your clips. I have an issue with a keyboard: a column of keys get lights but don't send a signal, the keyboard is Logitech G pro. I try to bridge but it seems all keys ( F7, 5, T, G, V and Space) are one link on the board. Do you have any idea on how to start this repair, whats spares should I look for. This issue appeared after I try to resolder a switch ( I ve done this before, many times but never saw this type troubleshooting ). Thank you so much and Rock on!
Hello ! Adamant as I repair a diffrent type of board, based on inverter tecnology, that use to create a 3 phase output, in my experience when a mosfet fails or shorted the cause is alwayst the mosfet driver. maybe i'm not telling you nothing new, but who knows, maybe can help you. let me know... Also I really like your style in repairing and its very similar to mine, continue like this, and enjoy the work you love.
you may not get many viewers that will stay and watch the whole video, but those that do stay greatly appreciate your hard work!!
81 comments but no comments let me fix that
Nice video, thank you very much. May be as an idea, I saw some similar videos from Russian guys and they all told, that if on of the MOSFETs blew up, it is usually not sufficient just to replace it. In the best case it will work for another week or so and, in the worst, like in yours, it will blow up immediately again. They say, that if you have to replace a MOSFET, you always also have to replace the controller, because it usually is the reason, why the MOSFETs blew up in the first place anyway.
I think you're right. This video ended up being super popular, so I might take another swing at this, just to see if we can finish the job. It'll be a while though!
Good advice.
@@Adamant_IT Yes, i also believe the controller has turned on both mosfets (high and low ) at the same time, creating a path to ground through the low side mosfet probably, blowing the high side one. Replacing the controller too, might solve the issue
@@gaspardeelias2485 You mean NCP81174?
@@yosuhara No - its the mosfet driver chip Adam mentions: NCP 81062 from ON electronics. They are available from Aliexpress.com
Links to the ON datasheets site: www.onsemi.com/
www.onsemi.com/pub/Collateral/NCP81062-D.PDF
www.onsemi.com/pub/Collateral/NCP81174-D.PDF
Apparently the mosfet driver chip fails by turning on the lo-side mosfet simultaneously with the hiside mosfet, thus taking out the weaker of the 2.
I CANNOT TELL YOU how GOOD your content is ... and more importantly, how SUPERIOR your educational value is to anything I've seen.
YOU ARE REALLY AMAZING. MY REGRET IS WHY I DIDNT FIND YOUR CHANNEL EARLIER!
A GOOD CRAFTSMAN ALWAYS SHOW HIS MISTAKES SO WE ALL DONT MAKE THEM! YOU ARE EXCELLENT EXAMPLE! REALLY LIKE YOUR TROUBLESHOOTING CYCLES!
Dude, this is epic. I never knew it would be such an emotional roller-coaster. Haven't watched to the end yet but I'm rooting for you
I am watching you solder at 2am and find it fascinating. Love your videos 👍
I’m watch these every night before I go to sleep. Wonderful info!
"we did actually burn test this one" You sure did! 🤣
darn it to late to make the joke xD
should have found it earlier xD
Quite literally
Oh yay! I just watched the ghetto fix and was hoping there was an update video, and behold, here we go! Thanks again for the great content!
I have tried these MOSFET replacements and failed each time. But I never tried to dig that deep and improvise. Thanks for very interesting video!
I always watching your videos, and thank you that u mentioning the degree Celsius of hot air.
Make more videos where here and waiting and starting learning
Please try to do it you are the best guy explaining well throwing out lot of knowledge and experiment
I really like your channel as you don't floss over problems but show everything warts an' all, well done keep it going.
thank god for these videos. I have a evga 960 that had a similar meltdown, Inductors exploded and it shorted, and the fan bearing blew out. the blue pcb burnt to a brown color. hoping it didnt destroy the traces in the pcb, that will make this repair a thousand times harder... But i wanted to try and practise repairing components. And this video was exactly what i needed! thanks a bunch!
Lol i did the same thing you did too! I plugged the 960 into a lower wattage psu, a 550 and it took power and fan kicked on, just didnt produce an image.. so i tossed it into my system to be faster with troubleshooting and plugged it into a 850w and suddenly i smell a burning smell, the fan is twitching and came to the conclusion my 850w surged into the card and fried a bunch of stuff.
"It's Turbo dead! Ohhh Nooo" thank you, thank you, Thank You!!! I will be bogarting this quote over and over. Thanks for being human!
In my experience (not specifically related to graphics cards), if your MOSFETs short, you should assume the drivers have been damaged and replace them as well.
Great video. Know how buck converters work, but never though about how they're used for multi-phased VRMs. Thanks for the education.
That was really entertaining. Shame it didn't turn out as you hoped but hey, after all the replacement surgeries and explosions you still got it to work. That's a big win in my books. Keep it up! :D
Thank You.
And yes, learned alot (and I was sure I knew everything🙄). I enjoyed the magnum length video version. I ordered a pizza and told my GF to get lost. OK, I didn't do that.. I just let the air out of her 🤤 Anyhoot, you fought the good fight. Think I will pickup one of these classics. It will feel like an old trusted friend.
Cheers
🇺🇸😁🇬🇧
The fuck
I would guess the driver chip was turning on the high side and low side at the same time common issue with switching supplies
id love to see you fix some rx 570s an 580s i have a bunch i could send u man, i need fixed, but to see u do it would help me fix mine i love how u go over everything an explain it, SO AWESOME MAN i love you!!
Thank you for the details and explaining clearly how all this works. Very helpful. Would like to see more.
I paid 15k for electronics school and I learned more in this video than I did in 2 years at school.
Very nice video. I learned a lot I found an ATI RX series card in my closet going to try and fix the short with my new machine.
Interesting look into buck regulators. The only thing you didn't try was swapping out the driver i.c. I think that was faulty (thermally unstable) and provided the path to ground for the high side f.e.t. The driver i.c. probably switched the f.e.t. on for too long, killing it.
I dont have a desk top pc. Mostly laptops I own.. but as a electrical technician.. this Is informative and interesting to watch
Boy, (i'm 63) you have done a good work. It will be that you not have fixed the phase, but for sure you have teached something of english to me!
Bravo, Graham! Super informative and entertaining.
I like your videos very much. Your speach is 98% understandable for a non native, non supreme speaker :) You can teach me electronics - in English! - That is way more rare than you may think...
I love the cheap compact testers/o-scopes. However in this case I'd love to see a decent analog scope, at least in an educational video. Just constructive criticism. Nicely done though.
True that, he's getting confused a lot just because the scope is limited and doesn't show properly what's going on.
I think he should see full 12V on the mosfet output, mosfet is either off - 0V or on - 12V, it should not show anything in between.
@@Arek_R. That's not actually true, with such high switching frequency you can't constantly hold 12V or 0V at the output, I will always be something between. And for such purposes there will be no difference between cheap and professional o-scope, only slighly change in readings accuracy. Personally I use ad1102ca from Atten which isn't either cheap or expensive, but didn't notice difference when compared to cheap ones or some high end for thousands of $ ;)
The difference isnt accuracy. The sample rate / memory depth, determine what can be displayed on the screen.
Love your determination and commentary.
Terrifc video learned a lot . I am playing around with some ebay failures , Looking into reflow if no obvious failures.
50:20 i was so happy watching this moment your way of explaining things is amaizng
I watch your videos like i watched The Shawshank Redemption or other great movies :))Imagine in high school i was the electronic class and none of those teacher talked like that and was so boring.Now...i watch with big curiosity, you explanation are so good and i understand no matter if my english is bad. :)) GOOD JOB!
Great demonstration of how buck regulators work in real life. 👍👍👍 After theoretical explanation in a couple of previous videos it's nice to actually see it "in action". 😊😉 Thx for the effort.
that was crazy long and so educional video ! Respect for making videos like this to people understand little more more stuff :)
Been at NorthridgeFix , felt guilty so checking in. 😂😍
Wow, this came full circle! Good info though!
I DONT USUALLY STAY FOR THE LONG VID....but i was fascinated so I finished the video
Please use Flux and see the magic how your soldering will be ! For soldering and desoldering use Flux please ! Very good informative videos I am so thankful to you for your effort and work!
Best regards,
Thanks for your videos. I'm really getting interested in electronic boards and their components now :-)
Still, a great vid. I had no luck trying to replace a broken off 3.0 USB header pin on an older ASUS mobo, by desoldering/soldering (plan was to us a leg from a LED) but still felt satisfied with my effort in trying.
Thank you for the interesting lesson.
you have exactly the same multimeter as me xD
Man, I'd love to work in a repair shop with you, haha
Another great informative video, please Sir keep them coming but also please don't endanger the lives of yourself or your staff
I'm a retired electronic tech from the USAF and I've seen a capacitor test good but then go short. Replacing the capacitor corrected the issue of a system blowing a fuse. I'd say replace the Q1 cap even if it tests good.
Watching ur vids and I really love the learnings I've been picking up.
I got a gtx 1060 3gb faulty.. No visible defective part but I am not certain ofcrs.
I wonder if u can make a troubleshooting video how to identify shorts opens and defective part esp the critical parts.
I would and I guess most of us ur followers will really appreciate that 😊
🙏🙏🙏
Hi I am loving your videos on repairs keep them coming.
How ever it is not really a VRM, that term was used when the voltage regulator was on a small pluggable module, hence Voltage Regulator Module.
I am guessing the the topside FET is not switching properly maybe the bootstrap capacitor or driver IC is not working properly.
The input inductors are only for EMI reduction, if they were not fitted and it went short all that would happen is the PSU would go into chirp mode assuming you do not have any other components in the board that would fail 1st.
I believe the weird chirping you saw on the scope was a sign it was not switching correctly, and the waveform on the output of the FET will be a pulsed one from GND the 12V, I am assuming your pocket scope cannot display the correct waveform.
I have a GTX 970 looks like liquid damage , short out PC . Happy to post it for a attempted diagnostic video
I find it funny that right after I left the video and commented you need to read schematics, you start looking at schematics.
Albeit not the card manufacturer schematics.
I wonder why? Also critical because the phase ground didn't end there, couldn't you have traced it farther?
I do understand though you showed how you can figure out without schematics what goes where, which is handy if it is obscure or old, but that card wasn't either.
Can't you get small business loans to cover ultrasonic cleaners and Schematics websites?
I can't find them for free but idk.
Thanks, this was awesome! I learned a ton. Entertaining as well.
Forget your Kyles, Jayzs and Linusus.... This real IT problem solving! I wouldnt attempt it myself though... My clumsy fat fingers wouldnt be able to be this precise
Interesting. Just a warning: You should put a metal piece between the alu caps and the hot air to prevent heating them too much.
On top of the great content in your channel, I love your English! 👍👍
Agree
Sir, it's 3:48am in the morning... WTHECK just happened.. all I heard was turbo dead.. Mosfett just dropped dead!!
😂R.I.Pieces Mr. Mosfet.
Sorry sir, I was quite happy for your accomplishment. Use the donor card.. what else can work as an inductor replacement?
Dr. Frankenstein we need an Abby Normal Brain.. A better Mosfet that can handle a fuller load. This way the resistors can still take care of some of the flow.
Man you are the teacher I never had🤗
These two pcb's are absolutely identical, I bet down to even a single wire and its physical pos. on the pcb, so it is highly unlikely that that you couldn't take any individual part and exchange it between the two pcb's - with only one exception - if the two boards has significantly different timing specs.
Just about all semiconductor manufactorers have don those designs since the mid 60's and Intel, AMD, Realtek and yes Nvidia and ATI too - you get a complete design with schematic diagrams, BOM and most often even Gerber and drill file.
I once had a collection of 8 different MB's that original was a Intel BX-440 - only difference was the color of the solder mask, occasional different color of a connectors plastic (never the position) and the top silk screen that stated the name of the OEM - as I remember ASUS, MSI and First apart from Intel, I can't remember the last four :-)
They were carbon copies of each other - except from major build quality variations ;-)
If you have time a nice video would be one where you show how to test each item and what it should look like if it is good. I have several bad video card that I purchased trying to learn. I took a power supply and put 5 volts and 1 amp into the back video card 6 pin plug and tried to follow where the voltage stopped. I jumped the mosfet gates with 5 volts to try to get the mosfet to turn on, and in spots it did. Ground on one side of caps but got no futher. A video starting at the 6 pin and checking each item saying what you should see and what you did see moving along would be great. You know what things should read and jump right along, but a video for more or less beginners step by step would help alot of people I am sure. Thanks for your time and videos.
Could you please tell me the value of the input inductors? I need to replace the blown ones.
Brilliant info - really useful and educational... many thanks for taking the time to share.. Subscribed ! :-)
Graham bro, you are really awesome.....
Fantastic video!!!
"the short magically disappeard" :D There's no magic, the problem lays in the method you use to solder the mosfets (or actually any QFN-type components with thermal pads), placing to much solder on pads and then trying to push it out is a bad idea, 'cause you push it in all 4 directions, 3 visible and also the one that goes to G and S pads of the mosfets which you can't see but for sure will make a short circuit ;) So in my opinion it's better to clean the pads from old solder and use solder paste (even some cheap chineese one), SnPb is preffered (by me) 'cause of lower melting temperature :)
@1:09:40 you start thinking why it shorted again and burn upper mosfet while it has no connection to GND, it's all caused by failed PWM controller and/or driver which drives low side mosfets constantly so at output you have GND all the time and when swiching upper one it simply burns out ( double lower side mosfets can handle that short, single upper one will blow up)
Bwahahaha, it thinks its consuming 400watts :D. Yeah that shunt resistor soldering was nice :)
So very interesting video. Very educational.. i injoy watching.
Very interesting video!
More please !
at the start of page 13 of the datasheet at 21:57 sec, it's clearly written "if a phase is unused, the differential inputs to that phase's current sense amplifier must be shorted together and connected to the output"
Well spotted - that might've been the purpose of the resistors around the unpopulated driver chip.
It's hard to imagine it's worth your time to attempt to repair a 960 board. I don't know about the U.K. but a board like this is worth about $150 functioning, it seems like too much time and effort for not enough potential reward. Anyway, I really enjoy your videos, keep them coming!
cleaning with isopropyl alcohol will help a lot and I believe that part that you did not know what it did is some kind of a boos or buck converter for voltage depending on the configuration.
How have I only just found your channel?!...I'm just waiting for my graphics to come out of the oven.
Very good try. I really enjoyed this video. Thank you.
awesome video! ive got an rx480 im trying to fix and this is super helpful.
How can you be so cool?! Thanks Sir!!
SUBSCRIBED! Keep up the good work and Thank you for this information! :)
Thanks very good and nice video I learnt so much from you.
Thank you so much!
I really learned a great deal!!!👍🏼😎👍🏼
Videocard resurections.. Nice man
Did anyone else notice that one small black component, likely resistor, moved off one pad when you first removed the shorted MOSFET in previous video? Then solder wick ate that half loose component while you cleaned pads of the shorted MOSFET. Would be interesting to know whether that missing resistor next to the blowing MOSFET affects something there and could cause the blow-up instead of damaged driver chip. I've actually found one Matrox Parhelia in scrap pile that smoked MOSFET of one GPU power phase shortly after it booted with good picture. Likely the reason was that one small component got misplaced on the rear side in that phase when the card got under many heavy devices deep in scrap pile.
Your efforts are really interesting and full of knowledge. I have got sufficient knowledge of lap tops. Can you share me the use of schematics of lap tops.
3rd LFC video and i learned a lot already.. subbed!
Why this youtube only recommend your video just now?
"Lets go death or glory" Please make a shirt. I would so buy it.
I did learn a lot from this video, thank you.
TBH I had hopes on the repair of the donor board too!
i got a gtx970 that set on fire, i had it water-cooled but the pump died. there are a couple of scorch marks on the water block it looks like a couple of tiny diodes. i might have to give this a go at some point.
I just works on same reference board with exactly a same issue (except mine go nuclear around inductors so it need some PCB etching and I end up replacing them with fuse as only three spots for inductors survive blast) and yes, I end up replacing control IC because first mosfet blow up few minutes after replacing. Now it work ok. Probably original problem was IC and not mosfet same like in your case.
for me, you are a real genius, and people told me that am genius am really an amateur compared to you.
Question is.. have you tested the coils which the mosfets are working together with? If they all have the same characteristics to different frequencies, or if other components have measured values slightly off specs. It's a longshot, but it might be the cause of why it's the first mosfet that shorts, if the harmonics might be off tune causing standing waves, or if some other component interferes.
I was thinking, maybe you could trick it into running 2 phases instead of one at lower and moderate load to smoothen the transition to 3 (or 4) phases?
I really enjoy your videos and your waffling :)
I know this video is getting on a bit now but I just stumbled across it, and I couldn't help but notice that the electrolytic cap by the auxiliary power connector seems to have the polarity the other way round, just a thought...
Thanks for another great and very interesting video ! ;)
Why is C160 backwards on the card?
Try replace the mosfet driver of the bad phase, anyway you gained a subscriber
Good work, respect chap
Good video 🔥💥💥
love your videos adam but need to say tht the elastic tow rope example is verry wrong.an elastic rope would infact ad super speed to the car being towed and infact cause it to smash into the truck towing it.the toe rope needs to be solid so there is no force in towing.ive pulled hundereds of cars and just sayin.wrong example.that being said i have truely learned alot from you and your videos.bravo and keep it up your a great teacher..Robert Whalen.Ontario Canada
Really enjoyed this video. Thank you.
I just noticed this but I believe the capacitor near the input is backwards , it is the other way around on the donor card. 🤔
Thnx for sharing knowledge... u are great man
aewsome dude, keep it raining...
Man, i am not an expert, i do repair things from time to time, but your voice and especially your English accent, really make me watch your clips. I have an issue with a keyboard: a column of keys get lights but don't send a signal, the keyboard is Logitech G pro. I try to bridge but it seems all keys ( F7, 5, T, G, V and Space) are one link on the board. Do you have any idea on how to start this repair, whats spares should I look for. This issue appeared after I try to resolder a switch ( I ve done this before, many times but never saw this type troubleshooting ). Thank you so much and Rock on!
Hello ! Adamant as I repair a diffrent type of board, based on inverter tecnology, that use to create a 3 phase output, in my experience when a mosfet fails or shorted the cause is alwayst the mosfet driver. maybe i'm not telling you nothing new, but who knows, maybe can help you. let me know... Also I really like your style in repairing and its very similar to mine, continue like this, and enjoy the work you love.
I reckon you're right - quite a few people also saying it's the driver. I might revisit this card later this year when I've got the time for it!
Love this please do mode GPU repairs