Please help if you can. I had a previous 32 bit XP OS and I could not get the 64bit disk to do a clean install; it would reboot and get to the "press any key to boot from CD/DVD" but it would launch the existing XP OS instead. Bios is set correctly to read the first boot device from CD/DVD. Finally I tried to install the Win 7 32bit disk and it installed perfectly the first time; this is presently the OS on the PC desktop now. I have an AMD Athlon 64 X2 Dual Core Processor 4200+ 2.20 GHz (it is compatible for a 64 bit OS). Then I spent over an hour with Microsoft techs and they remotely checked everything, and it shows compatibility for 64 bit as a clean install (Windows Upgrade Advisor), but several boot ups failed in the same way starting the now new Win 7 32 bit; Microsoft tech conclusion - the disk may be defective. Well I got the new DVD replacement disk today and it is still failing at the same point. Any ideas or recommendations? I want to add more RAM and am at the limit with the 32 bit OS version. Thank you for any help.