I've got a laptop that I recently upgraded from Vista to Windows 7. It works a lot better now for a lot of things, but there's one problem I've had happen a few times that never happened under Vista.

When I put the system to sleep, then occasionally when I wake it up again, for no apparent reason, the screen's dim. Sometimes it's as if half the backlighting was turned off, and sometimes it's as if all the backlighting was turned off, all except for the mouse pointer, which remains as bright white as ever. Trying to change the screen's brightness does nothing, but rebooting fixes this.

Has anyone else seen this? Any ideas on what's causing it or how to make it stop happening?