Yes its best to have matched pairs especially with ddr2. As for 4GB of ram, you wont really utilize it. Vista works well with 2GB best with 3GB. XP works good with 1Gb best with 2GB. With you system and cpu, anymore than two GB would be a waste, unless like said before if you have onboard video. If so, then maybe 2.5 to 3 GB. Hope that helps m8.

 

For your system I wouldn't consider it worth it to go above 2. You can find some good deals on 2x 1GB twin packs on Newegg, just make sure to get something decent. I'm a fan of Corsair personally but there's a lot of other companies that make good RAM.

 

then i'll look into that,
2-1gigs will be cool,
thanks guys

 

In addition to the 2 gig RAM I run on my PC, I load in a 2 gig sandisk card into the card slot and that really speeds things up.

 

I'm assuming you're running Vista and are using the card for readyboost?