Better? 4x512 or 2x1024 (PC5400)

[Primus462]

I'm thinking about doubling my memory. I currently run 2x512 Kinston PC5400 HyperX in Dual Channel. Which would be the better upgrade (faster) if I want to add another Gig of RAM: an additional 2x512Mb or replacing it with 2x1024Mb or could I just add the 2x1024 to what I have already, which would give me 3Gb. What do you think? 2x512 would, of course, be cheaper. Is 2x512 and 2x1024 (total) overkill?

Thanks.

 

[Rugger]

3GB is overkill. Best performance would be from 2x1GB - it will let you run 2T command rate. Ebay the HyperX...