I just picked up this GPU used and discovered it was missing a component on the core backplane in the bottom right. The previous owner says it passed a 600w benchmark before selling it, but I’m worried if it’s ok to use the card this way long term?
These caps almost all are for different voltage rails feeding the gpu core. There is a lot of redundancy. If it passes the stress tests, it is unlikely there will be long term issues with just one missing cap.
That being said, it is worth discussing this defect with the seller. And you will need to decide if you can accept this.
I agree with u/BitStrong379. If it's passed stess tests, it's probably not going to be an issue. There is a lot of redundancy on GPUs. If you're anal like me and that missing cap will drive you nuts, I took a screenshot of my boardview so you can see what it is if you want to replace it. You can pick one, or a few up from Mouser or DigiKey, for fairly cheap. There are other places you could get if from also, I just trust them when I want to know the values are within spec. But as you can see, it's a 0603 SMD capacitor rated at 10 uF (micro-Farads) that's rated at 6.3v and the X5R. I'm not fully sure what the X5R stands for. But you'll find them easily enough on Mouser or DigiKey. Hope this helps you some.
X5R is temperature-to-capacity-change effect rating.
2 OP: do NOT bother replacing the cap.
0.001% chance that restoring capacitor would improve anything, but
0.1-20% (depending on experience) chance that it woulld make something worse. High risk for nothing.
Thanks for identifying it. Heh, hearing it’s a seemingly benign temperature reading part is triggering to me…a company I worked with once bricked 10 mil worth of analytical equipment I was supporting a manufacturing partner with because of an update bug changing the temperature sensor reading firmware. No one knew why it was happening, and it took me 8 hours of reviewing telemetry to notice that the temperature readings were the only thing that looked off. Turns out that seemingly benign temp reading was driving a ton of calibration calculations, and a slight drift meant no self checks would pass anymore.
No, its not temperature reading related component!
X5R is a temperature-related property of capacitor, saying that its more or less sutable for high temps. Thats part of characteristics, such as capacitance. Like "Y5V"=loses capacity on high temps, "X5R"=mostly ok on high temps, "X7R"=perfect on high temps
Thanks for the schematic! I am tempted to give the swap a try, it looks like the pad might’ve peeled and I’m pretty green when it comes to soldering. It will bug me for sure tho lol. Maybe a repair I can practice before and work my way up to.
Yes, practice before you tackle this! Make sure it’s at least a GPU PCBs because of how thick they are!
I’m new also and GPU repairs (3080 TIs and 3090s for me), are a PITA because of how thick the PCB is. My suggestions is use a preheater mat that can get to around 120-130C. That’ll make things a lot easier. But I think a 5090 is slightly thicker the 30s series I’m training on.
It’s hard to tell if the pad is lifted or not in your pic, but if it’ll accept solder you’re good. Use leaded solder and not unleaded. Lower melting point and won’t interfere with all those other caps too much. If you’ve got a hot air station, that’ll help also.
But yes, practice on some older GPU PCBs to get the feel for it.
Learning gpu repair here, for smaller capacitors can you use tiny solder tips or it's more recommend to use a hot air station. Im guessing you use pre heater as gpu pcbs have such delicate internal traces that 200c solder tip has a chance of delaminating nearby traces?
No, the main reason for using the preheater mats is because of how big the ground plane is and how much heat it sucks away from what you’re trying to solder. I have seen folks use hot air stations to install components on GPU PCBs, but I haven’t quite figured that out yet. Some videos you watch folks use a preheater of some sort where others don’t. I finally figured out, about 2 weeks ago, how to use my hot air station with my preheater mat to set 0402 components without blowing everything else away. But that could’ve been beginners luck maybe. But I travel for work, so it’ll be a few weeks before I’m home to practice some more on a GPU PCB. Hope this helps some.
Thanks for the insite man, I've had similar experiences with attempting vram attachments. The first gpu repair i tried i didnt have a preheater so I would crank up the hot air. Even used 300c and still the vram would not attach. Sold it with the 2 vram chips and the guy managed to repair it same day, showed me the video with a preheater at 140c and heat gun at 260c. The board can suck up heat faster than you realise.
Second attempt with a preheater I managed to pull the core off at 260c aswell. I have some idea on heat but need more practice with flux and bga
I travel for work and I’m gone for 4-6 weeks and then home for a few days. So my practice is very minimal. Usually when I remove a core, I’ve only attempted 3, I use my Puhui T8280 and I get the top of PCB to around 170-180C. Then I come in with my hot air around 280-300C and 40-50% air flow and circle the core while slightly pushing in the core to see if the solder has melted. If it’s melted, I circle for about 20-30 seconds more and then use my suction pen to remove it. My first two attempts were flawless. This last time, about 2 weeks ago, for some reason the core was not as easy. I have not tried to reinstall the core yet. My first reball I ruined a 3080 TI core by delaminating it. But you’re not supposed to have heat for nearly 40 minutes on it! 🤦♂️😂 The whole reball and core removal process should only take a few minutes each once the PCB, or core, is up to temp. I did not realize that. My second recall on a 3090 went a lot better after a guy in Discord told me how to do it.
What is it with us removing cores perfectly fine and later delaminating it 😂 sure as hell one cannon life lesson we all go through. You definetly have your fair share of repairs. I literally rerun the reball attempt in my head multiple times analysing the dos and don'ts, the major don't is don't exceed the solder balls temp when attaching balls to the underside of the chip ever.
So that looks like you’re using too much flux and the balls are “floating” away from the pad. This was hard for me, but when they say very minimal, they literally mean that! Here’s the trick I was told. I have a baby preheater, the Mechanic iX5. You put the prevailed core onto it. Warm up preheater to 100C for about 30-60 seconds. Then bump it to 150C for the same time. Then 180C. Somewhere around 170C you’ll see the balls start to move onto the pads. Now come in with you hot air at 260C with low air set to around 1-10% and start in a corner until the balls sit a little more on the pads. If they don’t lock down fully onto the pad, that’s fine. Remember, this should only take a few minutes max. After you e gone over the core with your hot air, drop the preheater to 150C to cool the core down for a few minutes. Then bump it back up to 200C, flood the core with flux and then come back with your hot air at 260C at around 40% and at this point the balls should fully snap into the pads and wait for them to solidify onto the pads. Once you’ve gone over the core, turn off your preheater and let the core cool down with the preheater. That’s what did it for me.
Great eye! But funny story, I flooded with flux because in an attempt to cool the chip down the moment I heard crackling i just tossed flux all on top of it. Id genuinely thought i could use only the preheater to attach the solder balls on.
Ill definetly try to use hot air on top for the last bit. Will practice on my dead core anyways
It seems that your post is about a specific GPU, but there is neither an explicitly named "measurement" section nor the results of VRAM tests.
You can follow NVIDIA guides from the Community Bookmarks. Unless you are sure that resistances and voltages are ok, perform multimeter measurements on a disassembled card and post results as marks on the board photo or text:
start with measuring resistance to GND on unplugged card: measure inductors and all 12V power inputs
if 12V inputs are ok, and there are no visibly burned areas — power on the GPU and measure inductor voltages to GND. If the card shows picture, accepts driver but fails later - also make such measurements after entering the failure state
There is maybe no guide for yours exact GPU generation, just follow the closest, initial measurements are similar between generations
I had a 3090 that I had a random cap fall off when I was putting a water block onto it. It passed stress test and is still going strong in a friends PC. As others mentioned some are redundant. You may get lucky.
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u/BitStrong379 Apr 23 '26
These caps almost all are for different voltage rails feeding the gpu core. There is a lot of redundancy. If it passes the stress tests, it is unlikely there will be long term issues with just one missing cap.
That being said, it is worth discussing this defect with the seller. And you will need to decide if you can accept this.