Bugger it, Same has happend to me.
I flashed to the Asus top and now I have to use Rivatuner to underclock the memory below 850Mhz to stop any artefacting.
Tried all the other Bios versions but its no better. I think as others have found there is a change in the timings for the newer cards. (I hope)
Has anyone got both the 011.0.16.000.025 master and slave bios versions they can send me.
I'll remeber to send a Crimbo card for the help