Need an Experts Advice....

Hi,
i just bought an extra pair of ram to increase my current ram to 4gb.
my previous pair was
corsair pc6400 (5-5-5-18) @1.8v
and the new one is
kingston pc6400 (5-5-5-15) @ 2.0v .
Now since i have upgraded i had BSOD on a few occasions. I been using corsair but never had a BSOD before also i tried running Kingston on its own for a while but didnt encounter any BSOD either.
So i checked in the bios and both modules are running at 1.8v i think its something to do with the difference in voltage as kingston is being under powered .02v. If i go ahead and change it to 2.0v in bios will that have any negative effect on the corsair.
I will also try running memtest later on during the day and post it here.

here are my specs

E8400 CPU
680i SLI Mobo
280GTX 1GIG
SB Audigy
Corsair 650W PSU

When you were running the Kingston sticks by themselves were they at 1.8v or 2.0v? If they work fine at 1.8v (they probably do but it's not a certainty) then I would look into giving the MCH or whatever it's called on your board a small voltage boost as running 4 sticks at 800MHz is hard on the memory controller.

If the Kingston sticks do require 2.0v, you could probably get away fine with feeding the Corsair sticks 2.0v as well, but again it's not a certainty and it's your fault if they fail under those conditions... They probably wouldn't, but you never know.