I had Windows 7 7000 on my tx2500z (on a partition, with the Vista installation still intact), and it kept randomly shutting off. Not shutting down, just completely powering off. I have no idea what was causing this, but yesterday I formatted and installed Windows 7 OEM x64. The computer is still randomly turning off. I have used this laptop very little since I purchased it, but wondering how this issue would persist after a clean install. Has anyone else experienced this? How can I determine what is causing it?