Win7 x64 fresh install, 11.7 driver, SDK 2.5.
Hashing with cgminer2.2.1. The shares output shows all HW errors
On the same machine, if I use 12.1 driver and the SDK that came with it, it hashes fine. But the hashrate is low with 12.1 driver and the newer SDK.
But if I remove the SDK, and use the older SDK 2.5, it would show error again.
Same machine and GPUs also hash fine using BAMT. So I am sure it is not a hardware problem.
GPU is 5850 with two 5870. I have tried with just the 5850, and the result is the same.
Screen flicks one time when cgminer is starting. This happens on both 12.1 driver and 11.7 driver. But in 12.1 driver, it hash just fine.
Any ideas? Offering 1 BTC bounty to whoever solves my problem!