Well you just have to go in your BIOS (reboot and keep the DEL key or the key to access your BIOS) pressed down.
When you are in your BIOS, depending if you have an AWARD or AMI you should just go you your CPU settings and lower the temp there.
Note: if you keep you PC in a warm area and do a lot of multitasking, the CPU temp. will likely stay warmer. Keep it in a cool place, keep it clean and you shouldn't have any problems. Lowering a few degrees will just make your fan work harder!
