How VRMs work (I give up edition)
ฝัง
- เผยแพร่เมื่อ 25 ต.ค. 2016
- The basic principles of how a motherboard or GPU VRM works.
Patreon and Shirts: cxzoid.blogspot.co.uk/p/paypal...
The Twitch: / buildzoid
The blog: cxzoid.blogspot.co.uk/
The Facebook: / actuallyhardcoreovercl... - เกม
Tried to search for an explanation about this last week and couldn't find one that this non-physics-expert person here could be bothered to understand.
I undestood, so it was effective!
Gratz!
Linus Tech Tips brought me here to this old video but I've been a subscriber to Buildzoid for years. 😎
I've watched this video before, but nice to see LinusTechTips give it some love in 2021.
Link
@@sheepslayer649 Sorry man, I don't recall which video it was. Unfortunately TH-cam just says, "1 year ago".
I wish he'd have touched upon the subject of auxiliary phases and why they're useful (or not useful). Most high-end motherboards have a +1 or +1+1 setup, but the Z790 Apex has a +0, and despite spending hours googling for answers I can't find any information on the advantages / disadvantages of either type of setup.
@@VVayVVard Most of the material I've seen on auxiliary phases refer to different devices on the motherboard (or at least different domains of the main System on Chip). For example, the main VRM number is the Vcore rail (that feeds the CPU cores), so an 8+2 phase VRM has 8 Vcore phases.
The auxiliary phases however will be dictated mostly by the platform (AM4, AM5, LGA1700, etc.) and the chipset. Then you get separate VRMs for things like Vsoc, Vgpu, Vmem, and so on. Which rails exist depend on whether that platform and chipset have them or not.
For example a Z790 board could have a 12+0 VRM because the CPU takes all 12 phases from the motherboard to power its own internal voltage regulator for cores, gpu, i/o and so on. Compare that to a Z590 board with a 12+2 that has similar 12 Vcore phases, but the extra 2 phases feed Vsoc or Vddr for the memory, since DDR4 modules don't have onboard voltage regulators like DDR5 does.
LTT Floatplane sent me here, and I'm glad I came!
Fantastic explanation, wish my college professors taught this clear.
A video like this that explains GPU architectures. What's the difference between Cuda and GCN architecture in terms of circuitry? Why is one better at geometry (for example) than the other. What makes it better at a certain task. How do ROPS theoretically etc affect FPS? I would watch the shit out of the video.
Anyone else?
Same but with the right background of knowledge it's a Google search away
GN did a nice video on it th-cam.com/video/x-N6pjBbyY0/w-d-xo.html
have fun
When profesor on uni explains it.. booring.. almost sleeping on the table.. when Buildzoid explains it.. wow, this is so interesting...:P
Anyone else coming here after Linus's video?
"why are so many normies in the comments" - BZ, probably
Been loving your content for a while but not long enough to see this video. Be prepared for a load of views as LTT linked you in a new video.
I've never taken the time to learn about electric currents, so this is a very helpful and education video, even if it's the 3rd time you tried to do it. Thank you.
"Wait, so that's all just PWM?!"
"Always has been."
It‘s pwm with extra steps
after watching this video....
+15 INT
If someone have basic knowledge of passive components it's perfectly understandable! Great job!
Get ready for some LTT people coming to this video. You just got a shoutout on floatplane!
Good explanation. Thanks for taking the time to put that together. I like the combination of the schematic and the voltage graphs.
Learned a lot. Love the rambling. Half the entertainment value. I am sure that I'm not the only one. Keep it up!
We love you. The messiness adds charm.
Subbed.
(I had no problems understanding your video, though I think mid-tower cases are gaudy enough we don't need to shove 10s of amps through an LED.)
thanks man! i love these explanation videos, they compliment your gpu pcb reviews very well because i can now properly understand what you are talking about.
Thank you! Exactly what I wanted to know for months to understand the pcb analysis better!
Great video! Thanks!! Please do more like this explaining how stuff works and also how to calculate load :)
Excellent video man!
Watching your channel for quite some time now and this video demonstrates why. Awesome job!
God damn. Around 18:00 when you said "this is a single phase vrm" everything just clicked. Fucking simple. Thank you
Nice overviews and understandable illustrations. Very informative for me as a layman.
Thanks for this, it really helped me to understand how VRM works.
I would like to see the third power phase added just for the sake of better visualize the "voltage curve" and also explain the timing (open/close) that is a little bit more complicated on 3 phase. Very nice video, thank you!
Wow, I actually understood it!
The messiness might have actually made it easier as I was more focused on the content rather than the aesthetics of a neat handwriting and drawing.
This is good info, like exactly what I wanted lol. Not just VRMs regulate your voltage hur dur... But an actual breakdown of the components and how they interact with almost proper drawings :D
Hi. Just found your channel. Brilliant. Thank you for sharing. Precisely the right level of technical content. Will be binge watching your vids. Many thanks for your channel and content. A few more will be joining after your praises have just been sung. Amazing 🤩
Excellent exposition. Subscribed!
Voltage is also called potential, like a rollercoaster on top of the ride versus being after the drop. Potential energy converts into kinect energy. Same principal. Ground is a reference point of 0 to measure against. I dunno if that helps anyone follow
Dayum, I've never seen a truly legitimate use of the bar going through 7s until now. Kudos, you've proven there's a reason to do this :)
Well now i know exacly how the vrm works! thanks buildzoid!
Thanks for explain how low side mosfets work. Exactly what im looking for :)
Thanks, this channel is exactly what I was looking for, great explanation keep it up! Tech Gaming Weekly brought me here.
Very informative, thanks for sharing!
Excellent video for noobs like me always interested about that but never dug as deep as that in the components :-)
props for this!
What you actualy made in this video is an current regulator. The inductors try to keep an constant current flow and not voltage. This means that if the gpu resistance would change so would the voltage(using this system). That is why normaly there are capacitors behind the inductors to keep the voltage more stable.
So what you would actualy do in a VRM is use an mosfet / transistor / switch to charge a capacitor to the correct voltage level. The inductor is there to prevent the capasitor from charging to 12v instantly(much like you explained in the video).
Mark Prins I just wanted to cover the absolute minimum of components to lower voltage ignoring the fact that a cpu doesn't have a constant current demand
Nah the inductor and 2 MOSFETs on their own would manage that as long as the load didn't change. So if I replaced the CPU with a resistor that graph would be valid. The problem with CPUs is that they need 100A one moment and 50A the next and then they suddenly need 150A. In such a scenario what I drew would overshoot the voltage hard when the current demand goes down and deliver too little voltage when the current draw goes up. If you added capacitors they would store extra power so that when the current draw goes up instead of the inductors running out of power the capacitors would take over and when the current draw goes down the caps would store the excess power that the inductors are trying to get rid of.
doesnt the choke induce the current into the other direction?
edit: nvm it only the voltage... the current flows in the same direction
Awesome video and really clearly explained. Thank you!
BZ, i have no practical reason to watch or like or enjoy your videos, but somehow I’ve been systematically perusing them and hitting highlights still effective, relevant, and essential in 2019.
At first it was a mobo review that immediately changed my shopping cart in newegg. Then it was the same thing about the 5700 brand i was looking at. Now im a week into watching you and GN, and JaysTwoCents and you guys have changed how i fundamentally look at computers. Thank you. Im a fan and will buy a tshirt in appreciation.
Also new tshirt logo should be your google choke comment. I laughed really hard at that.
Oh and i do enjoy and find them highly entertaining. Why i have a sudden fascination with mobo vrm layouts and gpu vrm types is very confusing to me, but i’m loving your materials. Keep it up!
this is amazing you should do more of these
I like the way you explain things.
Thank you for your educational videos!
I wish I had discovered this vid so much earlier.... thx a lot!
Wow, this was a really entertaining and educational video. Thanks for doing this!!!
"I give up edition" O.o
Welp, This should be interesting....
Good work man! Hate the graphs but well explained.
Just would like to love seeing some filtering caps in the next video!
/Fellow Enthusiast and soon to be Electronics Engineer.
I left out caps because I wanted to keep the video somewhat short. They are of course absolutely key for a varying load like a CPU but I didn't want to have to bother with them for the sake of explaining the absolute basics of how to go from 12V to 1.2V.
After running across your video on the misrepresentation of VRM phases by Gigabyte, I found this one on VRM basics. Your clear and easy to follow explanation of VRM basics has provided me with an understanding of an area of motherboard "jargon" that was totally unfamiliar to me. As a relatively new PC enthusiast, I'll be hunting through your library of similar videos on related topics to help me further my understanding of the electronics behind my MB. Thanks, your efforts are very much appreciated.
you need to give yourself more credit you go way in depth with this stuff and explain stuff that no one else dose. been subbed ever since your PCB analysis of the reference rx480 and have watched every vid since. now i'm confident on getting a waterblock for my ref rx480 and might get another but i might just wait for vega.
Actually others explained the stuff too. But another viewpoint allways hels to understand, when the story is told by another person. However i also think he doesn't give enough credit to himself.
Linus Tech Tips pointed out your page and I am glad they did. Good job in an explanation VRM and other items.. Thanks!.
Vary good Vid BZ. I understand/learned alot of your VRM lesson. Your drawings great. inductance. reluctance and field collapse are weird science to me but your circuit diagrams helped.
Best back converter explanation on youtobe. Good work!
Great explanation. Thank you so much!
This video is pure gold ty
This was actually really good. I now know that diodes aren't just light bulbs that burn out really quickly. They actually serve a purpose. lol
Good content on this channel. Cheers man.
thank you! great vid, as always.
Now i understand. Excellent video. Good job.
Fantastic explanation. Thanks.
Awesome info! thanks for the video on this!
Thanks, really like your explanation.
How the hell is that this youtube channel is not very popular while he is so unique in his subjects!!!
Very interesting stuff! Thanks for explaining :)
Suprised I hadn't already found/watched this, but it's exactly what I was looking for, thanks,
Also, I was both educated AND entertained :)
A great video this is. Thank you.
wow i am an electrical engineer and i know how critical are this things to learn. But your explanation is very easy. hope people will enjoy such technical terms ..
Off - "Googling choke gives you a pretty hard time" - LOL, that was epic!
that was simply awesome :)
After the "failing" vedeo, it would be great to see the "how processor (CPU/GPU/whatever) frequency generated" :)
Dmitri Weissman You use electrical resonant circuits
Thanks man.. big love
This was legit educational, thank you
First off, thanks for the video. It definitely helped me understand VRMs and how they function on a basic level. Applying what's in the video here, when a GPU blows its mosfets, that is in most cases the lowside mosfet and the diode in particular, correct? The diode gets to a point where it cannot dissipate the heat coming off the inductor and efficiency begins to break down entering a runaway thermal scenario. I realize there are quite a few more components at play here, but I assume this is a basic explanation of what's going on, right?
Nice and easy to understand. GJ.
Very well explained!
Good video. However the voltage at point B is also filtered by the bulk capacitors. Just as an inductor doesn’t like changes in current, a capacitor doesn’t like immediate changes in voltage. As such, when the main switch turns off, the voltage at node B will not tend to increase because of the output caps. It will be the voltage at node A that will decrease until it goes below ground at which point the diode (or body diode of the synchronous MOSFET) will begin conducting.
yeah I left out the capacitors intentionally when I made this video since what most people can't wrap their head around is how an inductor makes a chopped up 12V into a lower voltage. The capacitors are of course absolutely necessary in a real world application but for the sake of not making this video even longer I left the capacitors out.
Good info. would love to see one at failing point if can.
I'm looking into getting a some GPUs with dodgy VRMs and blowing them up in the near future.
Actually Hardcore Overclocking Get an 8800gtx, set the fan speed to 20% and run furmark. 720p was enough to blow mine up.
Furmark with low fan speed is cheating. I want to do it properly. Water cooling on the GPU core. Lots of airflow over the PCB and way too much Vcore running 3Dmark.
Actually Hardcore Overclocking A custom BIOS on a 290 running 1.5V with no vdroop? I know the 290's VRMs are strong but I can't remember how strong they actually are... need to watch your video on the 290/X PCB again :P How about the 480 with overkill vcore? No amount of airflow can prevent a VRM blowing up from too much voltage.. right?
i wanna see the wattusage of the 290 then, before it blows :o
This is some usefull information. Can't wait for some xfx rx 480 videos from you.
Shift+Ctrl for aligned lines :>
I could have used this video years ago when a pretentious head of the electrical trade school told a couple hundred people in an address to the new class that there was only such things as single phase and three phase, and that 2phase was a Batman villain. I'm sure the director would have appreciated the public rectification and acknowledged my precociousness
sounds like he was talking about 3 phase power
Thanks, based Buildzoid
Thanks for the explanation man, more like this video please :)
Shared this with my friends! :)
I have never found electronics wildly entertaining unless im changing some caps out to vintage mustard caps in my marshall 100watt tube head.maybe tweeking the tone controls.adding a pot for feedback more or less in the circuit.Building tube amps has its fun but like anything its weird floating grounds.Keep up the good work
Nice video. Good job.
Awesome vid. Would there be current between the inductors as there is voltage difference between them?
Well done. Really nice percentage of likes/displays (if you take into consideration that it's not very entertaining topic). So CONGRATS! :)
Thanks for the video. I was wondering about my CPU power phase control after watching your recent zotac 1080ti video when you were talking about frequency, and mentioned higher frequency gives a more stable voltage, where as lower freq is more efficient.
After watching this video, my understanding is that increasing my "CPU Power Phase Control" setting in bios increases how often the peak voltage (let's say 1.4, the voltage my 3930k needs for its oc) is reached, and reduces the dips between, and lowering frequency slows the switching between phases, increasing the amount of voltage dipping.
Is my understanding correct?
If so I hope I can increase this setting on my motherboard and hopefully lower my CPU voltage a little without sacrificing stability.
Thanks for the video
Great video thanks
Thx dude , this is great
happy i found this
Appreciate you video and understanding of the collapsing field around the inductor. Kinda lost me when you illustrated current flow from GND to 12V through the diode. I’ve always understood current flow through a diode was - to +, cathode to anode, unless you’re talking about hole flow.
Both holes and electrons contribute to positive conventional current flow through a diode
Thanks!
Sangat membantu, very helpfull tutorial i was ever seeing
thank you
This video is so easy to understand and great! It's pure philanthropy from your end! Great job!
Thanks for the video. How to determine the the current rating for vrms with high and low mosfets from a spec sheet they are assigned different currents unlike integrated drivers with a specific Idcmax.
AWASOME video,subbed
Very informational. But you could probably do this a lot better with a program like Multisim or another similar program because then you could have actual voltages and currents and be able to show how the circuit really works in real time.
Thanks for the Vid.
I was actually trying to make sense of the V A W info in hwinfo64....AMD x570 Board with 3700x cpu
How the PPT at 88W, EDC at 90A burst and and TDC at 60A sustained work together with the VRM.
This is what I think is happenning.
The VR_VIN is listed as 12.312 which I assume is the ATX12v on the rails to the CPU Core, SoC IO.... (& MEM NB MCH Not shown in hwinfo)
This lists....
VR_Pin_CPU at 60W
VR_Pout_CPU at 47.5W (app. 79% efficiency)
VR_Pin_SOC at 15W
VR_Pout_SOC at 11.5W (app 77% efficiency. So I assume this is actually 80% efficiency like most PSU)
....which is where I get stuck on how 60W+15W = 88W ????? ....unless there is even more power loss somewhere.
Which brings us to the missing info if I am on the right lines.
DDR4 Ram apparently uses 5/12W per GByte @ 1.35V so that 32GB installed DDR4 = 13.333W @ 1.35V (11.852W @ 1.2V)
Here then, 60 + 15 + 13.33 = 88.333W PPT
...which means the more RAM you have, the more power its suck from the Cores and SoC power with an 88W limit.... and reduces the CPU performance ???
So added to the VRM list above shoud be...
VR_Pin_MEM at 13.3W (or 13W integer)
VR_Pout_MEM at 10.7W (@ 80% efficiency)
Here 60 +15 + 13 = 88W
....if I am on the right lines.
What is preventing the 12 volt current from flowing through the diode when the 1st switch is closed?
Thanks for the great video!
Thanks man
Great video, thanks a lot :)
Actually, inductors charge up inverted exponentially (very fast first, then slower)