On Oct. 26th, I downloaded Win 8 Pro with the intention of using it on my main desktop machine. I have XP and Windows 7, Home Premium on this machine also, on separate hard drives. The machine runs those 2 operahttp://www.techrepublic.com/forum/discussions/102-396192ting systems very well. After installing Win 8 on a separate hard drive, the machine only ran for short periods of time and rebooting because of errors. If I am reading the messages correctly, they seem to be memory errors. After trying to remedy the problem for several days, I gave up. This machine is a home built computer. I have an Asus P5QSL PRO motherboard in it. I have a Core 2, Quad Core, Extreme processor, 8 GB of ram, and a very good video card. I tried to install the system on an older Dell computer, that I tested extensively for memory errors, with Memtest 86. I tested the machine for over 4 hours and had no memory errors at all. I had the same problems with Win 8 on that machine also. I finally installed the system on an older HP laptop and it runs OK on this machine and I haven't had any problems with it in over a week. I am at at loss as to why Win 8 will not stay running on either one of the other two computers. They crash in moments, or sometimes an hour or so later, but they always crash.