I just completed a BIOS chip upgrade (failed BIOS flash, had to install a new BIOS chip) and noticed a problem with the CPU fan. When booted, the fan mounted on the CPU (PIII, 500Mhz, Slot 1) kicks in and operates as it should. As soon as the OS loads, the CPU fan stops. I have yet to observe the fan working while installing the hardware, software, and testing the machine. At first, I thought that "maybe" it wasn't needed under a low processor load... so I tested my theory by burning a CD to force the processor to put its brains to work. - an alarm sounded, and I quickly shut down the computer. (I did set the CPU to shutdown in the BIOS when the temperature reached 140 degrees, so I hope I wasn't a total idiot by testing my theory!) I can't find a setting in the BIOS or the OS (Win2KPro) that controls the CPU fan... anyone have any ideas? The fan does work during POST, so I'm assuming at this point that it isn't a mechanical failure... I'm thinking it must be a BIOS or OS issue. Thanks- Karen Wasson PCBUILD maintains hundreds of useful files for download visit our download web page at: http://freepctech.com/downloads.shtml