I've been trying to troubleshoot this problem here
It seems like this may be a hardware issue. I need help to determine the specific cause of the problem.
In brief, the hard drive test showed no errors (results posted in other thread). The notebook had it's hard drive wiped with the diskpart clean all command. I installed 2 new memory sticks to no avail. Right now, I'm trying to install the operating system again from a genuine Microsoft installation disk, but the PC crashes on the "windows is loading files" screen. (Disk works fine elsewhere.) It doesn't get to the initial screen on the disk, much less the options to repair or install. If left to boot to the HD it says, "bootmgr is missing". Memtest86+ still crashes the PC with the brand new RAM, but it gets a little father than before and crashes in test 3. If this is a hardware issue, how do I make that determination, and how do I troubleshoot the exact cause?