After install of Win7 to an old Gateway 700LTD, it won't shut down and just restarts when clicking Shut Down, Sleep, Hibernate or using the Power Button to shut down. I have to do a hard shutdown at the point where it restarts. This is an older machine which could not boot from disk, so I pulled out HD and used another PC to install Win7, but drivers were easily adjusted when I reinstalled HD and it is working well, even the ancient 64mb NVIDIA MX400 video card took it's XP driver. All BIOS settings are returned to default, I tried troubleshooting various fixes got from Google, then decided to determine if it is a Win7 issue by installing another copy of Win7 on a second test partition, which also won't shutdown. Don't you think this eliminates the OS settings as the culprit? If it isn't the OS and BIOS is set to defaults, then I am thinking Power Supply or CMOS battery failure. Any other ideas?