It looks like we use the same models of RAM sticks. As for temperatures, <40ºC sounds very low. C2D/C2Q overclockers generally let their load temperatures reach 60ºC - 70ºC, and it doesn't sound likely that Phenom II can't at least get fairly close to those temperatures without resulting in a thermodynamical cataclysm. I think you can push your vcore another 0.5V without much additional risk. However, you should probably procure some 1066 MHz Corsair sticks (e.g. PC3-8500 if your motherboard can handle it) if you want to overclock it a bit more.

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