Thanks Patrick
Indeed it must have been the MB CD because I never tinker with drivers or hardware (never oclck) when not knowing what the consequences might be. I followed your instructions and suppose the 2009 version is now installed.
This is something I have been repeatedly trying back 4 months ago when I had the problem and STILL the old GC (GTX 295).
Back then I must have tried a good dozen of drivers from 2 years old to the last to a beta. It never solved anything.
Here I remind that 3 days ago when the problem reappeared I have been using 311.06 which was not the latest. That's why my second action (just after running MSE virus check ) was to go to the Nvidia site and to install the latest driver (320.49).
The weirdest thing here is that as soon as I changed the GC 4 months ago, everything has been working fine during 3 months with a non updated Nvidia driver (311.06) and even with the hopelessly old Asus driver that you mentioned and then the same problem suddenly reappeared despite the fact that I changed, installed or updated nothing. As a summary - the problem appeared with an old driver 311.06 and continues with the last 320.49.
Download Memtest86+ here: Done. As I have neither an empty CD nor an UCB key, I can't run the test yet.
