First, let me get this out of the way: I'm running a peltier - have been building and running peltiers for nearly 5 years now so am basically a guru. My problem is not directly related. ----------------------- This Celeron2, 900 is OCed at 1.2G. Normal temps under W98 have been in this range: CPU - 66 to 71F CASE - 85 to 91F All very acceptable and expected. Now, using Same computer, same setup, and same MBMonitor(5.1.0.2), but with XP - Temps are in this range: CPU - 32 to 35F CASE - 85 to 91F I have verified these cpu temps with a probe. Under XP, the cpu temps will rise to a normal 66 to 71 if I put my UD program in the background to utilize all otherwise unused cycles. Running the cpu at the nominal 900mhz makes the problem even worse. Obviously XP has some sort of built-in app similar to cpuidle or rain! My problem is: temps this low are dangerous as they encourage condensation. My rigs are designed to keep cpu temps above dew point at room temp. So, does anyone here know where in XP I can turn "off" the switch that causes the cpu to do a HALT command during idle cycles?

Why dont you just turn off the peltier?

Here's a better idea. Get something like Motherboard Monitor (search for it on Google), and set it to start crunching numbers in the background if your CPU reaches a certain minimum temperature. That's what I have on my peltier-cooled system, to prevent condensation.

Sorry, missed the part where you mentioned you were already using MBM. Anyhow -- just set up the feature that lets you crunch numbers to heat up the CPU if the temp gets too low.

"set up the feature that lets you crunch numbers to heat up the CPU " This is a good temporary solution, which I'll initiate. Thanks for the tip! I'd still like to find the feature in the System Idle Process that's calling the Halt command. That would be a more permanent solution. Anyone?

I think it's just hard-coded into the System Idle Process, so you may be stuck there.

Yes, XP featuers the HALT command for the CPU! So basically there are only 2 ways to get rid of this! 1st: flash your Mainboard with a bios that has the HALT commands disabled (though unlikely u find one) 2nd (the one that works 100%): reinstall XP while having ACPI deactivated under Bios options! If u are the "standard PC" layer rahter than the "ACPI PC" layer, you wont have HALT commands available for use! But be aware that you cant use Standy or Hibernation anymore! Shutdown will still work if you activate it on the Energy App, called "APM"! Anyway, I do not think that you can use a software to turn it off, as it its part of the Kernel running!