Stick of 512 PC3200?

After my system started freezing up due to a lack of system resources, I thought it was time to get some more RAM and upgrade from a previous stick of 512... So now i'm looking for a new stick. I have a Corsair Value PC3200 512 stick in, and i'm pretty sure it's unbuffered pin 184... I was looking at a Kingwin for 72 bucks, because that 8 dollars means quite a bit...

lots of unkowns here. if you want to run dual channel tho, you should try to get a matched set of 512s.