You're not the only one ... from what i have gathered it is hapening to lots of people running any of the last few releases of VCC.
On my main rig i am running 12.3 and all is good...
On my gaming rig i have tested 12.10 and 12.11 beta and having flickering issues.
Its not hardware related because my rigs share the same hardware. Something is broken in VCC ....
Pics of my rig
FX-8350 @ stock, custom water cooling, 8Gig Corsair Dom 2133 9-11-10-27, Asus CH V Formula, SilverStone ST-1500 PSU, Auzentech X-Fi Prelude, Logitech Z-5500D , 1 x Water Cooled HIS 7970, Asus VW246H Monitor, Win 7 64Bit HP, Corsair 800D Case