My Computer is OPTIPLEX GX620. I decided to buy 2GB ram and add it to computer.
I was hoping to be at 4gb, but didn't realize the 4 sticks already in my computer were .5gb each.
Long story short. My computer has 3GB ram. 1gb, 1gb + .5gb + .5gb.
However, it says 3gb installed. (2 usable)...