I have a Lenovo N200 laptop and have re installed Vista Home Premium recently. It now intermittently Powers off on the Vista loading screen when you turn the machine on. It also intermittently powers off when resuming from sleep mode. It does not restart, it just powers off. If it successfully loads windows it runs fine. I have re installed vista several times and ran the unit with no drivers installed, minium drivers, any driver / utility Lenovo recommends and it has not stopped the issue. I have completed RAM tests, Hard drive tests, re installed the CPU with new thermal compound and it still randomly powers off on start up. I have ran the unit with no battery installed, with no psu plugged in and it still presents with the same problem.
The thing is, if it was happening randomly when the machine was running I would have thought it was hardware related but the fact that it only happens on start up suggests it is software related. I have just enabled the boot log but typically it is loading ok at the moment.
Anyone any ideas?

Try ubuntu.

mine runs cool on ubuntu without any funny issues.

you need stability and windows aahhhh.???