PDC2G4000ELK

[frozndevl]

I just received my RMA for this memory, the first set had one dead stick. I have installed it, manually set the timings to 3-4-4-8 and attempted to run memtest @ 250mhz. When I go into memtest and attempt to configure, my computer reboots. Can anyone suggest to me why that is? Is this indicative of a bad set that I should RMA? Here are my system specs:

Abit KN8-SLI
AMD X2 3800+
Antec NeoHE 550W
EVGA 7600GT KO