I have this machine in my office that's been sitting quietly under a desk for a long time.

I'd decided to re-purpose it for IE6 compatibility testing and since I had it configured to auto-update I need to re-install Windows XP.

It made me wonder how long it had been running there and whether or not there is a way to find out what the origional install date of Windows was.

It turns out that SystemInfo.exe does the trick !