My random crash problem returned this week. I've given up trying to find what's causing the problem. So, tomorrow I'm going to format my hard disk, and do a clean install of Windows. I'm almost certain these random crashes aren't being caused by a hardware fault, so a clean install should cure the problem once and for all.
And that's not the only problem I'm having with my machine, either. My Zalman CPU cooler has now started making funny noises when it starts up! And if that wasn't bad enough, I still can't play any intensive games or applications unless I take the side of my machine's case off due to the temperatures getting too high. Argh!