Going back to your original post the PXE-E61, PXE ROM was a boot drive issue. However, the powering down may have been an over heating or thermal protection cut out from the fan failure.
It may have been accidentally toggled to external monitor, try [Fn]+[F5] a few times to cycle through the options. If that doesn't work, you could try hooking up an external monitor to see if it's the graphics chip or just the laptop's display - just don't leave it running for long with the fan not working.