I ve got a Mega PC 651 with an 1,7 Ghz mobile Pentium IV-M in it. Without modding the CPU it runs on 1,5 volt, and 12*100 MHz. I made the "bent pint trick" to make it work on a lower voltige, to generate less heat and to be quiter. Now it works fine at 1,1 (1,08-1,09) volt. The 1,7 GHz mobile processor rated voltage is 1,3 volt, but it works fine at 1,2 Ghz with 1,1 volt too, and generates very little heat. In this way the cpu cooler works only when the CPU it is on hevy load (for example, when I use Power DVD). At this voltage, I can even overclock the CPU to 1440 MHZ, but 1,2 ghz it is fine for DVDs and internet browsing. I even tried the 133 fsb trick, isolating the Pin AD6 with nail polish, and it works fine at 1,48 volt and 1596 Mhz, and overclocked even at 1,7 ghz (142 Mhz fsb).
BUT, I have got a problem.
The Mega PCs CPU FAN turns on regularily only when the CPU heats up to 45 C. When I turn on the Mega PC, the heatsink turns on for 2 or 3 seconds, then stops until the CPU riches 45 C, after hevy CPU load. My problem is that, after working on Mega Pc, with the fan running very rarely, sometimes after I turn off my PC and some other times turning it on again, the CPU fan starts to run constantly at high speed, and never wants to stop. The Speedfan program and Fuzzy Logic, reports high temperatures 53-60 C, instead of 21-22 what it shows normally (they are incorect, the cooler is not hot, not even the CPU), I dont know why.
Could you help me to find out why it is happening so. Speedfan ver. 4.28 reports at Fan1 and Fan2 high temperatures. The CPU seems to be at low temperatures. Inspite of this the FAN runs constantly at 3,800 rpm. The Bios also reports low CPU and motherboard heat. Fuzzy Logic overclocking program also reports high temperatures right after I start my PC. I have to restart my PC, after it starts to run normally.
I can find out why is this happening. Please help me if you can!!!