Getting 2 Gigs of Ram

[tornadog]

I have 2 x 512 pair of Kingston HyprX Ram. Thinking of getting 2 x 1G OCZ Platinum. Can i add the 2 gigs to the 1 gig to have 3 gig or just keep the 2 gigs. Will I notice any performace improvement having all 4 sticks or will they create issues because they are not identical?

 

[vanvock]

4 sticks will run at 2T