I have just build a Pc with Intel D945PSN motherboard, Intel processor (Pentium 4 3.06 MHz, LGA775 package), 2Mb dual-channel memory (all 4 slots) in an Antec P150 case. I did not use additional thermal grease between the processor and fan. The cpu fan seems to be securely attached (locked) to the motherboard.
Additional components are an SATA HD, floppy amd CR-RW/DVD-Read IDE Drive. Power supply is ATX12V ver. 2.2
With case fan (92mm) at high speed and the case side off, the PC shuts down after a few minutes with a thermal shutdown message. There was no speaker sound(siren sound), before shutdown.
The processor zone and two temperature threshold zones are clear of cables and air flow does not appear to be restricted.
Now the interesting parts:
(1) The above ocurred in my home office (cooled @ 73 deg.) with the Antec case side off. What follows is with case closed.
(2) Running the PC in my workshop (not cooled, 5 degress warmer) for an hour the shutdown problem did not occur.
(3) Running the PC in my home office *and* booting from WINXP Pro installation CD,the shutdown problem did occur when windows was starting.
(4) Running the PC in my workshop *and* booting from WINXP Pro installation CD,the shutdown problem did occur when windows was starting.
(5) Running the PC in my workshop for a couple of hours with no CD the shutdown problem did not occur.
I have looked at http://support.intel.com/support/motherboards/desktop/sb/CS-012552.htm
, Intel Desktop Boards Thermal Zone Information. Except for BIOS update and Intel® Active Monitor (can't install), I believe all conditions are met.
What's going on (cpu working harder at boot?) and how to I fix problem?