when you finish with ur bios settings do you hit f10 to save and quit. If not reset ur jumpers and do ur settings in bios and see if it saves.
So you've checked the FSB with CPUz or the CPUs frequency? If it's just the frequency you are checking it could be because the CPU is reducing it's clock speed because it is idling.
Try replacing the CMOS battery. The CMOS memory holds the BIOS settings that you define in the BIOS setup program. This memory is powered using a battery so that the settings are not lose when you turn off the power to the system. Many motherboards do not test the status of this battery and will just indicate problems with the CMOS memory when the battery fails.