Okay, we've got a Dull in the shop, which is mostly used by the "office manager" to play solitaire...
I plugged it into the new network.
Hard, no warning, power down reboot crash after about 10-15 minutes. Rebooted fine.
Does this repeatedly and consistently.
Fine.
I plugged a wireless dongle into it, fired up the warez, hooked up to the network, and fired up a browser. CLICK. Instant power-off crash.
Any ideas?