Hello,
So this is a very strange one..
I have 6 GPU's all running fine for nearly a month hashing at 710kh.
I had a windows update issue, and driver update etc. It caused some BSOD's etc and would fail after only a few hours.
Once I had cleaned up the mess I had 5 cards drop to 80kh/s where they were once 710kh/s!
That forced my hand to reformat, fresh Win8.1 Pro, drivers back to the way it was a month ago.
When I went to start mining again, I suffered the issue again.
5 Cards @ 80kh and 1 card @ 710kh/s
![](https://ip.bitcointalk.org/?u=http%3A%2F%2Fi.snag.gy%2FAapvC.jpg&t=665&c=Cpv9Kx0uw6kmug)
Has anyone suffered this?
Any troubleshooting tips?
Thanks