Chosen Solution

My Mac Pro 1,1 (upgraded with 2,1 parts) has a problem with the fans. Every time I turn it on, the fans slowly go up to maximum speed until Windows or OS X boot, where I can slow the fans down with software (Macs fan control). The CPU and GPU aren’t even hot in boot up, staying at about 30-45 degrees Celsius on boot up. What could be causing the fans to speed up that much on boot up?

If you can, find a way to clear the CMOS. It’s possible the CMOS is making the fan run at full, but that’s all I can think of.