Watch this before replacing fans on your graphics cards

Inno3D 3090 came in with a note saying that original fans were making noise so owner replaced them with aftermarket fans found on aliexpress.
After that, card no longer worked and ended up on my bench just to verify that it may very well be the fans that killed this GPU.

If fans were not properly wired, 12v will shoot into the core via 10k resistors and thats most likely what happened in this case.
I dont know 100% but this is my best guess given the circuit design and its lack of protection from such scenario.

For repair, please contact me by following the link in the channel ABOUT page.

Tools, schematics, boardview files etc are available here

[AndrewFremantle]

I've done fan replacements before, including installing aftermarket heatsinks and installing larger fans onto them. I've been lucky to never kill anything, probably because I always try to verify the pinouts involved as I work.

I did not know that connecting the 12v VCC to the PWM line could blow up the card. It makes sense, I've just never thought about it.

[ActuallyHardcoreOverclocking]

I don't get why the fan would come wired in such a way that it could bridge 12V to the other pins. The pin out for the fans is supposed to be 12V PWM RPM and GND (I don't remember the order). I could understand if the sketchy fans just didn't have a PWM or RPM connection at all but why would there be 2 12V connections?

I'd be far less surprised if the 1.8V rail just shorted out on it's own for no reason because I have seen pex do that on some cards.

[grandrei]

i once bought another set of gpu fans and i installed them the other way when i fired the pc on the fans bursted on fire and melted but the gpu was still alive i guess i was lucky

[doktorvga]

Hey Tony!
In this case if you measure the Ali fan assembly's 2nd and 3rd pin you are most likely to find a short between them because of a solder blob messing between them or just poor soldering stuff.
The problem is that the pin number 2 is 12V and the third is GPU Tach which is go directly into the GPU.
I got the same card for repair months ago with the same story and the same problem, that 3 leg and the GPU went to the other side immediately when the customer pushed the power button on his pc after replaced the original fans with these s***.

[releon]

new subscriber here, Binge watching all your videos right now. I learned and entertained on how you fix GPUs. Keep it going.

[DrathVader]

Gotta be careful with parts from China. I ordered a display cable for my thinkpad x390, it came and fit perfectly, except for the fact it was wired completely back to front, ie pin 1 was pin 40 and vice versa. Shorted the 19V backlight rail to ground. Blew the fuse on the motherboard, but thankfully I managed to fix it.

[eqfpjwg]

Wow. could say that is very bad luck if the fan shorted to pcb. This should thou basically lead to question. How the fuck they design those fan circuits on the cards. And how that's even fucking possible. Thats fucking ludacris if fan 12v can short the core or memory like there isn't any fucking protection on the fan circuit?

Specially if you think how often fan's tend to break up on cards. And people replace these fans bought from china all the time.

[MikeZak]

well at least the noisy fan issue has been solved permanently

[tech.curiosity]

WoW, i can feel the owner feelings (disapointements, regrets, madness, sad) he have learned in a very hard way.
Thanks for the video that may save somebody else.

[ShannyTindall]

Yep, you totally can kill your GPU replacing fans. Exact same story here.
Fans became noisy -> bought replacement fans from eBay -> replaced and powered on -> dead GPU -> repair shop couldn't fix it so it was doomed.
I'm sorry this happened to someone else. I learned my lesson that day to never touch anything again and leave it to the professionals lmao

[zf]

I bought so many fans from Aliexpress & replaced them on so many GPUs! sometimes you need to check the fans if they work properly or not though didn't had this situation before.

[Del_UK]

Would it be possible, for you to test the connections of the fans? Is there a difference between the Inno 3D fans and the replacement fans? 🤔

[AbdulMunemChung]

I find your videos therapeutic, love it! Keep it up! Much love!

[markr]

So sad. I am super cautious about pin-outs! I had to make up a power cable the other day, to power a Quadro GV100. I joined two six pin cables to one 8 pin cable. I spent ages checking and double checking the 12v and Gnd were correct. I have been doing electronics for over 40 years, and I can tell you - you only get one chance with that much current!

[TheMeistermeister]

Wow. The lure of cheap prices for a quick fix can cost you more. Thank you for the warning.

[kathrynck]

I would really have LOVED some detailed close-ups of the fan pin wiring, and showing what was wired wrong, and how one could determine that before installing.
Cuz frankly, where are you gonna get a fan which _isn't_ made in china? The OEM fans are usually made in china.
I mean, "check redit or discord"...which redit page? What retailers?
Sorry to seem frustrated, it's just that I have a 1080 Ti Strix OC and a replacement fan (amazon) sitting on the desk, right now. And now have no idea what to do with them.

[enkur]

so the hotspot was on the core when you checked under thermal camera? wasnt quite sure why this was unrepairable

[rustygear]

He should consider himself lucky. This 12v injection could have taken down his entire setup.

[Revoku]

how does a manufacturer make something so bad that a bad fan can screw up the gpu core? thats insane considering how cheap and avalible fan control IC's are with all the required parts and protections internal to the IC.


what happens if a stock fan craps the bed, overheats a winding and gets a short? dead gpu by fan is just poor design choices, what did they do, run a controller that communicates over i2c to have the bios control the fan speed via pwm but were too cheap to get a controller that has the power circuit for each fan channel onboard along with the required protections and went with an external transistor for power instead?

[harlequintheserpent]

Once upon a time an AIO pump got seized in my PC, shorted, and blew a fan driver out.
The BANG was horrendous! System shut down. It could be the end...

However, the motherboard (A-Zeus X99 Pro) didn't give a pecker and still runs to this day just fine. Except for that one fan header.

Since then I've elected to go full custom loop with classic full metal jacket D5 and never trust those flimsy contraptions with plastic casings just awating some extra heat to expand and jam.