I have a Gateway notebook about two years old, running Windows 7 64-bit. About a month ago I booted to safe mode to run a virus scan and in the middle of the scan the system shut down, with no warnings at all. Just one second the system was on and running, and in the next second the system was completely off.
I can boot to Windows and leave it running for days at a time without any problem. When it shuts off in safe mode like this, some of the time it acts as if it was overheated and needed to be left alone for a little while before it would boot back up. I also tried running hardware diagnostics from UBCD and it shuts off while running these. However I can boot right back up without any issues or having to let it sit.
The appearance of overheating only will happen when the issue occurs in safe mode, and then it was only noticed about half of the time. A normal boot into Windows or Linux has no problems and can be left running for days at a time. If it was overheating the issue would not happen under specific conditions, as far as what I am running, and would happen even when booted to Windows normally.
I have also checked the Event Viewer and can't find anything of use. Does anyone have any suggestions? The machine is still under warranty with Best Buy. I currently have them looking at it, recently asked for an update and found out that their hardware diags all passed. Found out the information I was given by Best Buy was wrong and it kept shutting off in their diags and it was shipped out.
--Tom thanks for editing but some of the changes, changed what I was saying or made it sound like it, to which I adjusted those areas to be clearer.
-- Tom and Breakthrough : Don't assume overheating because I mention it, it is not consistent enough, in that it only shuts down in safe mode and while running diags, and only when the symptoms exhibit in safe mode when it has acted like it was overheated, and then not all of the time.