As for your CPu temperature problem, just buy a new / bigger / copper Heatsink and fan (or CPu cooler) yes the older athlon originals and athlon XP's were made to withstand higher temperatues, my old 1333MHz T-bird Athlon ran at just under 70 Degrees C idle and 78/79 on full load, and as far as I know it still works today (As I sold that computer to somebody who lives down the road )

Newer CPu's shouldnt see more than 60 Degrees C, and definitely not over 70. 45 - 55 would be an ideal temperature for a fairly modern CPu, hell my Athlon 64 3200+ here, overclocked more than 25% (2GHz - 2.51GHz) runs nicely at 38 Degrees C idle and 54 at an absolute maximum under heavy load for hours. And thats on a small AKASA copper base but mostly aluminium heatsink, with a 50mm fan with auto speed sense control.