First off before i post my problem I will post my computer specs: 1.9ghz athlon xp 1.5 gigs of ram A-bit nf7 mother board audigy soundblaster pny Geforce 256mb video card 500 watt power supply Windows xp sp3 160 gig WD 7200rpm 40 gig 7200 rpm If there is anything i missed please let me know thank you!! Ok so i have recently boughten 2 1 gig sticks of ram pc2700 333mhz!! After adding the memory i have had no problems with windows booting up!! the main problem is that windows likes to lock up or restart when running a program, or multiple programs!! I only use the computer to play counter strike or W.O.W or to look things up on the net!! So basically the computer has become unstable after adding the memory!! Right now i only have 1.5 gigs of ram it doesn't lock up as much but still does! since adding 2 seems to make windows lock up all the time!! Before i added the 2 gigs of ram i only had 768 megs of ram for the longest time and never had a problem of locking up or restarting!! I understand that alot of my computer parts are old but the motherboard says it can handle up 3 gigs or ram at once!! I have not yet re installed windows since i do not have legit copy!! Im just wondering if something is overheating or programs are conflictiing!! If you need more information i will be very happy to provide more!! This whole problem started after adding two gigs of ram!! I am running windows on 40 gig hard drive since i have no way of installing it on the larger hard drive!! I have heard from few that the locing up or restarting would go away if you re install windows!!