hello. i bought this comp. AMD3500+ sucket(939) Gigabite Mobo k8n nforce4 PCI-E 1024mb kingston and ATI X850XT . the problem is that after i installed windows xp and antivirus updated the windows from the web and all the pc doesnt work like it suld its really slow and some times its shuts down buy its self . i reinstalled the windows 7 times nothing helps . plz help me !!!