I was wanting to upgrade my memory from 4GB to 6GB, I have a ASUS P5N32-E SLI Motherboard and 4x1GB OCZ Special Ops DDR2 PC-6400 800Mhz, could I buy 2x2GB OCZ or maybe Corsair DDR2's and replace 2 modules with these, leaving me with 2 banks of OCZ 2GB and 2 banks of Corsair or OCZ 4GB, giving me 6GB, or can I not mix manufacturers.
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You can. The important thing is do you have a 64bit copy of windows? (Vista and win7 both come in 32 and 64 bit flavors) As long as you have a 64bit copy you should be good.
Thanks, yes I have Windows 7 Ultimate x64
Actually I was wrong about the memory I have in my system they are DDR2 PC2-7200 900Mhz, a bit strange since the highest my motherboard can handle is 800Mhz, maybe I can overloclock them.