Sun -- for a change, what about taking the easy way out? That thing is under full warranty. Call EVGA and tell them the truth, that your pc ran perfectly and for months at a time until this new card came along. Put it directly in their court and have them diagnose and fix it over the phone. It'll probably work, or you'll get a replacement card if that's the verdict.
On the slower smp work after a foulup, a cold boot should return the productivity on the cpu. Not ideal, but until this thing gets fixed, might as well finish out the affected smp work at full speed.
This will get fixed, Sun, but let's let EVGA do it at least at the front. Or see what they say, like maybe oh yeah, you need to blahblahblah. Anyway whatever it is, it's their job to fix it. We might all learn something too. Just a thought. Thenagain Micro might jump in and say first try this, and it'll work, we'll see.