The cpu alarm was a problem adressed by abit, so updating to the latest bios should fix it.
On another note, yes the prescotts run pretty high temps. they are not that great for overclocking unless you have very adequate cooling. DO NOT attempt to overclock them on stock heatsinks, as you will burn it out quite fast.
Also, it would be a good idea to check if the heatsink is mounted properly and such, although I think updating the bios might fix the prob hopefully.