I like Corsair. I assume you have 2x2GB and you can get 2x4GB to add to it. With an older AMD Athlon x2 system, it came with 2x512MB and I added 2x1GB, getting me 3GB dual-channel. It should work the same for you. btw G.Skill is also good, I've used them a little, though I have more experience with Corsair.