power supply can't cut it?

[RADEoN]

i recently built a computer for a friend, and it seems to reboot under any 3d graphics, i checked the core temperatures and they're staying around 47-53 and up to 58 under load from orthos.

Core2Duo e8200, radeon hd3870, 250 gb hd, sata cd rom, 4 gb memory PQI brand memory, and an ultra 500 watt power supply.

do you think that's it?

 

[device manager]

Please be more specific about which Ultra psu. Listing only Ultra is too vague. Can you run Prime95 or Orthos for 8+ hours without a reboot? Are you o/c'ing anything? Have you tried different video drivers? Did you install Chipset drivers?