bad video cards

[AmDD]

Ive got two video cards that have stopped working correctly. They lock up the system nearly as soon as cgminer starts. The cards are only a few months old, whats the process to return them under warranty? Im sure others have been down this road, im just looking for advice. The cards are Sapphire and were purchased from newegg.com.

EDIT: cards are Sapphire 7950's. Also I have replaced the stock thermal paste with AS5, will this void the warranty?

[PEBKAC]

First off, what makes you so sure the cards are bad? The fact that CGMiner locks up your machine doesn't prove the cards are bad.
Does a different miner work?
Can you still play games on those cards?
Have you tried to install the latest drivers, making sure you used AMD's driver removal tool prior to installing the latest driver?


And yes, disassembling anything on the card voids your warranty.
Did the problems start after putting the new thermalpaste on?

[chondrite]

are these the only two cards on the system? 

[AmDD]

The cards will not work in 3 different systems. (2 mining rigs and one gaming system). Each mining rig had a total of 4 cards (powered risers) and one card from each has stopped working. Removing these cards allows the remaining cards to function without issue. WHen these two cards are put in a gaming system they will typically boot the desktop but as soon as a game is launched it locks up.

The issue did start not long after the AS5 was applied, but it seems to happen too fast to be a heat issue I would think.

[kuusj98]

Look if you can find any blown Cap's or VRM's or any brown/black parts on the bords.
You would not be the first one to have problems with a Sapphire card, why do people even buy them? Becouse they are 2$ cheaper then a better cooler?

[SirMintALot]

Maybe you put too much AS5 on the chip? AS5 takes a long time to stabilze and is conductive. You can easily make short circuits with AS5 if you are not very carefull. Better use a good ceramic paste to be safe.

[AmDD]

I'll check for bad caps/etc this evening.

Ive never had an issue with AS5 before, it is the only thermal paste Ive ever used and have been using it for years. I'll double check that too tho.

thanks for the info

[AmDD]

I did not see any bad caps or burnt components anywhere. The AS5 if anything was a bit thin so I added a bit more (areas of the chip had none at all).

Im 45min away from my rigs and wont be able to try the card until next weekend.