Windows 7 needs more memory

Ok so i installed the windows 7 RC, I rather enjoy it. But like many have found out that running 2 gb's of memory and playing games like World of Warcraft. make for a terribad gaming experience. Due to limited resources atm, and limited knowledge of how things work in the memory world. I understand that you should not mix ram. However I am out of options. Primarily because, since moving I cant find my windows xp disc to reinstall it. So I'm stuck. What I have is.......

http://www.newegg.com/Product/Prod [...] 6820231098

http://www.newegg.com/Product/Prod [...] 6813131072

With an X2 6000 AMD

What I have laying around for a temporary solution is....

http://www.newegg.com/Product/Prod [...] 6820231047

However what I don't understand is the voltage, I have yet to be able to find the ram on g.skill that rates so high in voltage. And if it is correct, I misused that ram for years.

Either way, it's the only option I have currently (stupid recession). Is there anyway to make this work. And be stable?

the amount af ram you have wont affect the gameplay..windows 7 is much lighter than vista .i have 2 gbs in my system and i can playthat game perfectly fine .might wanna check your video card. ofcourse winxp is the lightest

Ya I wasn't going to put it in. Was just curious. As for windows 7 being much lighter. i'm not sure what you are seeing Ron. Running wow with the same specific addons and setup as previously. I'm using 70-90% memory usage. So it's not the video, or I would of had the same problems I have now previously. Which I did not.