I just recently purchased two 1gb ddr ram chips for my dell dimension 4600 desktop with windows xp home. I took out the two old 128mb chips and put just one 1gb chip in to see if it was enough to speed it up. I started the computer up it recognized the new chip but it would take forever to load windows, it sat at the load screen before you select profiles for 10 minutes, every process seemed to take 3x as long as normal. I tried putting the old ram chips back in but it still runs 3x slower then before. The new chips say "vista ready", but thats what the tech at compusa gave me, so I dont know. any help?