I've been having problems trying to play Unreal Tournament 2004 since I bought it. Within 10 seconds of starting a single player game, my computer would reboot itself. I perused these forums looking for anything that I could do to be able to play this game. I used MemTest86 and Hot CPU Tester Pro and got no errors at all while testing both the memory and the cpu. Always keep drivers/motherboard bios up to date so knew that wasn't the problem.
Then on a hunch I decided to raise the core voltage on my Athlon XP 3200+ from the default 1.65 to 1.75 and I've been playing just fine ever since. Don't know why this solved my problem but it has. Thought I would post to this forum in case others would like to try this also. If it helps one more person play the game without it continually rebooting their computer then I'll be happy.
My computer config:
Athlon XP 3200+
ASUS A7N8X Deluxe V2.0 Motherboard
1GB Mushkin Special 2-2-2 PC3200 Memory (2x512), Dual Channel Mode
Hercules (ATI) 9700 Pro Video Card, 128MB
Now it looks like the game stalls for a second or so every once in a while but at least now I can play. I'll take a small studder any day compared to completely rebooting my computer after 10 seconds or less. Again, hope this helps somebody.