I put a new CPU heatsink onto my Pentium 4 478 Processor. Dells are tricky because there is only 1 fan power outlet on the board, and it is not even a standard one, It is hooked up to a 92mm (38mm thick) case fan, which brings air into the machine, the power supply takes the hot air out, since the fan on the power supply is on the bottom. But anyways in order to get me CPU fan to work I have to run it off a molex, I have a convertor for it. Now would it be running at the full 12 volts? If it is could this decrease the life of the fan faster? It is an 80mm thermal take fan (TR2-M12 all copper heatsink). Thank You for you help it is very much appreciated, Jesse My Maxed Out Pentium 4! Dell Dimension 4600 Pentium 4 HT @ 3.4GHz 4GB DDR Ram (2x500GB) SATA II Drive Windows Vista Ultimate NVIDIA 7600 GT

It would be running at the full 12 volts and that's what you want.

All computer fans that I know of are 12v.

Are you sure about the CPU fan header? I haven't seen a modern computer that didn't have a dedicated CPU fan header. I am surprised is will even boot up. I suspect you have the case fan connected to the header intended for the CPU fan. Connect the CPU fan the the header and use the adapter on the case fan.