Low memclock evga 980 ti sc+

[Ken123]

Hello.
I`m learning electronics and graphicscards so im new at this.

I`m having issues with one of the evga 980 ti sc+ i repaired a bad mosfet on.

The issue is its terrible performance and i noticed memclock to be stuck at
405mhz. I tryed ddu, flash different bioses (even one from my working evga
card), checked voltages and seems ok but im no pro. The other card work as it should with same drivers/bios/computer.

I`m stuck atm and hoping someone have an idea of whats wrong.
I attached furmark test of both cards
/Ken

[akorede]

Re: Low memclock evga 980 ti sc+

clear the output air of the fan way

[Ken123]

Re: Low memclock evga 980 ti sc+

As seen on attachment for The bad card, its not getting hot. Also fans, sinks and thermalpads are good / ken

[manuforti1314]

Re: Low memclock evga 980 ti sc+

I always refer to Tech Cemetery on YouTube,

https://youtu.be/0HiXeF7RPlU?t=887

He has a card doing the same thing. Might be of help. Might not.

All his videos are very illuminating.

[Ken123]

Re: Low memclock evga 980 ti sc+

Thnx, but accually i saw that video. Its not the same issue unfortunally. His card cant detect memory type due to modification. My card detect memory normaly.

Only thing i noticed is that my card starts at normal clocks and also pcie 3.0. After a couple of seconds it drops memclock and also pcie to 1.1

[Ken123]

Re: Low memclock evga 980 ti sc+

Ok, for future reference.
I think i found the problem.

This pex voltage regulator? (Or display rail. Pls correct me) Was bad and shorting the nearby caps to gpu.

It did output 1,0-1,1 volt (same as my working card)

I have yet to assemble and try the card.

Check attachment for u502.

[Ken123]

Re: Low memclock evga 980 ti sc+

Well, i changed that chip and card only flinched at boot then was dead. I did some measurements and got to the conclusion that all needed voltages was present except pex. Changed it again and now voltage is present.
Tryed the card and wasent detected. Felt wierd so i tryed mine and it also wasent detected. Did I kill both cards when measuring? Is that possible?

Tryed a third identical card and worked fine.

[Ken123]

Re: Low memclock evga 980 ti sc+

All voltages are correct on both cards, tryed swapping bios chip and still same. I suspect i accually killed both cards somehow. I have one incident in my head, at one time i forgot to change mode on multimeter to voltage from resistance. But that was one instance. Both cards have the same problem. Both cards booted before.

Maybe i killed my own card and the other card killed gpu by it self when powerrails worked properly. Or i have made some fatal mistake when meassuring that i dont even know is bad to do.

Anyway at the moment no card boots, no gpu fan and not detected at all. Not even at twitch. Cpu fan goes high speed (not normal) but computer boots into Windows on internal graphics chip.

My guess is 2 bad gpus. How did that happen? ��

[dicky96]

Re: Low memclock evga 980 ti sc+

Firstly, forgetting to change you DMM from resistance to volts shouldn't cause any problems

Try diagnosing the problem from scratch - have you seen this video, it may help you
https://www.youtube.com/watch?v=SmVdl8kew_4

Rich

[Ken123]

Re: Low memclock evga 980 ti sc+

Thanks, thats a great video, love the channel. =)

havent found the problem yet and ran into same kind of problem with an ASUS strix gtx 970 but this time with coreclock. perfcaps pwr and clock lock at 202mhz.
feels like some rails can´t deliver full power at load. i need to figure out how to check that. could also be faulty gpu maybe.


could it be bad mosfetdrivers? cause i only changed bad mosfets

[fab13]

Re: Low memclock evga 980 ti sc+

Hello everyone,

I repaired a sapphire RX 470 4Gb it was an IR3553M HS phase controller mosfet on VCORE alone 1 and the board works in games again.

Except that during the FURMARK test I have frequency drops of around 300mhz then go back up to 1030mhz every 5 seconds or more when it turns at around 73 degrees.
The jerky image then becomes fluid again and so on as a loss of frames per second.

In games, it causes FPS drops from time to time.
It's not ideal during the game =S

[Ken123]

Re: Low memclock evga 980 ti sc+

I had no luck in fixing core clock, maybe a reball of gpu in my case could work or its a bad gpu. I almost change The whole board in testing purpose but same.

Memclock was fixed by changing memory chips even that i had no errors.

Your case isnt quite The same since it goes up sometimes but thats What i did.