I have a system with 1.7GHZ , P4 , 512 MB + 256 MB SDRAM I had some problems in XP SP2. The system began to restart sometime after booting . It also showed some Memory Access Error . After this I ran memtest86 .The memtest86 displayed lot of errors in the memory . I replaced the 256 MB SDRAM with 512MB SDRAM. But still the problem did not stop. I decided to format and reinstall windows. I used many XP cds to do tht, but after the formatting , when the file is copied it shows up "cannot copy filename" . Several files were not copied during the installation and the installation failed. I dont know wat the problem is. Also i cant understand how 4 cds fail . So i thought there may be problem in the hardware. Any suggestion to troubleshoot?