Sound's like a similar problem to my own with the A8v i had a gig 2x512 3200+corsair twinx 3,3,3,8 which turned out was'nt on corsair's compatability list and would'nt boot with a single stick but did using a pair.
I was lucky enough to swap that ram for 2x512 twinx ddr500 which IS on corsair's compatability list but still would'nt boot
using a single stick.
I'm pretty sure your ram is compatable check for yourself
http://compatible.corsairmemory.com/ maybe it's a problem with the A8v when running a single stick of corsair?
Also bios 1008"which im using" and 1009.04 beta is on the asus website for dl they may be worth a shot?
Good luck anyway! :thumbup:
AMD 3500+ "winchester"
A8V Deluxe bios 1008,
1 Gig corsair twinx ddr500 3,4,4,8 ran as ddr400 2.5,3,3,5
36Gig WD Raptor,
80Gig Diamondmax plus9,
Radeon 9800 pro,
Enermax Noistaker 470watt.