Never change a running system.
I felt tempted to upgrade AMD Catalyst from 11.5 to 11.6 (link at AMD). Afterwards GUI miner did not work so I removed and reinstalled the new version.
This is one windows 7 / 64 bit.
Since then my system is unstable.
This means: I get a frozen system in 10 - 20 % of the restarts and the system stops mining and freezes after some 8 - 15 hours of mining.
No error logs or events pointing out the reason.
I am not overclocking or otherwise provoking things and before that on 11.5 and the May (?) version of GUI miner everything was rock solid and stable.
Any similar experiences ? Any ideas ?