It did have XP on it, so here's some results:
E5200 280x12.5=3.5GHz This is an everyday overclock, simple, takes about 30 seconds to do and works 100%.
3DMark06 13,800 with GTS250. Ok for a mb + cpu combination under usd100.00.
Here it is at 333MHz, sitting there, doing nothing at 3.8GHz.
Couldn't get it to 4GHz. Ah, well, nevermind. It will take a bit more fiddling to get the 3.8GHz stable anyway. Certainly looks like the G31M-ES2L is the way to go for 4GHz. I'll have to be happy with my 3.5.