Big, spontaneous restart-style problem

[GrowlZ1010]

While playing Graal, my computer (1.3GhZ AMD Athlon, 256MB RAM, 32MB nVidia GeForce2 MX) will suddenly and without warning shut off. This only ever happens while crossing level links, and only ever happens when playing Graal... and it seems to happen across all servers - it's happened on Classic, Rudora, Era and Providence, amongst others. It doesn't seem to be dependent on a certain script, though, as I can enter any levels that caused the problem again and again and again with no discernable side effects.

What's really weird, though, is that the effect is EXACTLY as if the reset button on the front of my computer is pressed. There's even a little click noise, ScanDisk is disabled on startup, and it takes the same time for booting..

There's nothing physically wrong with the machine, and it can occur randomly throughout the day, at startup or at 11 PM, so it's not a problem like overheating. The power cables and everything are all fine. No other DirectX game - no other application, even - causes the same problem.

I have the latest Graal download at time of writing - v.2.1.7.0 - and am using all the most memory-efficient Graal options.

Is this a known bug, or is this something new?