crash diagnosis software for windows (7)?

Does there exist a piece of software I can leave running on my PC that will tell me what causes/caused a bluescreen when it happens? More specifically which bit of hardware caused it?

My computer tends to crash after about 6-10 hours of being switched on and I’d like to find out why.

Try WhoCrashed.

Windows 7 also has some built-in functions which you can find in Control Panel / Administrative Tools / Performance monitor.

If your system has hardware diagnostics, you might want to let them run overnight to make sure it isn’t a hardware problem.

You can also find system logs for Windows 7 (and Vista, and XP) in Control Panel -> Administrative Tools -> Event Viewer -> Windows Logs -> Application, which will give you normal logs, warnings and errors for applications. Action Center also contains rather terse information on crashes, but I’ve found it to be largely useless.