Problem with 7950 litecoin rig

[navidos]

Hi folks,

I have 5 rigs with 4x 7950 each, and one of my rigs turn to be pain in ass.

I have no problem with other four (4x Asus MB) and this one (1x Giga MB) with 4 xfx 7950 cards crash all the time on litecoin mining.
it has no issue with mining bitcoins but when i switch it to ltc it crashes no matter which setting I use.

The thing is after running cgminer, my CPU start to get busy with it and seems to get into a loop which leads to system crash. I can't quit cgminer
after running it and end task doesn't help either and CPU keeps busy with it till system freezes if I reset system while is in this loop. either it doesn't go
for reboot and stocks at log off page or even if it does reset it doesn't come up and need hard reset.

I have changed windows twice with no luck.

any advise?

[navidos]

Yes, I removed one card and it crashed again.
usually first card stay at 0 KH/s while others are mining at 600Kh/s and then it crashes.

[Mintcraft]

Hi,

That sounds like it may be a power regulation issue with your motherboard. Are you using risers? If so, are any of them powered?
4 GPU's drawing the 75 watt limit of PCIE slots can cause stability issues on many lower end motherboards.

Next I would suggest a driver issue. The high CPU usage is indicative of a well known driver combination issue. A quick Google search of known good driver combinations and a comparison to your drivers should eliminate this possibility.

If you have had issues like this from day 1, it is possible its a damaged GPU. To eliminate this possibility remove all but 1 card from the rig, and test each card individually. XFX cards aren't of the highest quality and its entirely possible that mining was too much for one of those cards (GPU's weren't intended to be run at full activity 24/7). In which case you should be able to get a replacement from the place of purchase.

Finally I would suggest swapping out parts individually with one of your working rigs, this will isolate the problem.

I own a mining rig as well (4x Gigabyte 7950, AsRock mobo) and have spent years building and troubleshooting computers so hopefully my experience proves useful.

Good Luck.

[navidos]

Hi and thanks for reply,
My MB is Giga 990FX UD3 and I'm using risers, none got molex power.

As I said, the rig was running for months on bitcoin and still is without the problem and it's
mining 24/7.

The thing is that it has the same problem from the day one i tried ltc on it and after OS and Drviers
changes and updates and reinstalls, same shit happening again.

[Mintcraft]

So it's your cgminer settings?
If you post what settings your running I may still be able to help