cpu temp too high

[Kegman]

I have win xp pro.
Antec smartpower 2.0 500w power supply
ASUS pa4s800 sis 648fx mobo
agp geforce 6800gt
3.0 ghz intel p4 processor
2 hard drives
2 cd/dvd drives

The other day I came into my room to notice the computer was off and the smell of an electrical burn was in the air. The motherboard light was not on and no power was coming into the unit so i replaced it with an antec 550w power supply. From here on windows would not always start, when it did my cpu processor temp reads at 156 F-161 F without starting up any programs other than firefox. I thought the 550w may have been too much, so i bought a 500w again, which is what i had before and that didn't solve the problem. What could have happened and how might i fix it.

[MeestarK]

Have you made sure all fans are running? Have you made sure your fans aren't clogged with dust? Have you removed the heatsink and reapplied new thermal paste to it?

[Zogo]

the last couple times I've read heat problem threads it's been dust.

[Janus]

how many fans does the case and and what direction and they pushing and pulling in?

[Kegman]

i have the heatsink fan, and a fan in the back blowing out. no its not dust. I removed the old paste, put arctic silver on it. No idea what do than to replace mobo

[thrash_head]

I highly doubt that the mobo is what is heating your cpu up. have you tried to open you case up when its cool in the room and see if that helps? If it does, id suggest re-doing the airflow in the case.

[Janus]

or adding to it actually. But I would follow thrash'es advice and try just taking the side off of the case to see if that helps, even adding a small fan to the outside blowing in to see if that stops the problem. If it does, then you have narrowed it down.

[Kegman]

whatever the case might have been, the new mobo solved the prob. whether the thermostat was malfunctioning or something else, the new board works fine at this point.

and yes i had the case open making sure everyhting was fine and dandy.