Intel Core 2 Duo 6750
Kingston 2GB DDR2 667Mhz
Western Digital 500GB
Asus 8600GT (o'ced)
Anyway, CPU-Z indicates that there is:
1) a voltage fluctuation. It goes around 1.2V, but it's changing quite a bit. Is there something wrong here?
2) This CPU is rated at 2.66Ghz, but I've got about 2003Mhz listed as core speed, but this fluctuates to ~2.66Ghz now and then. Multiplier is 6, bus speed is 334 and rated FSB is 1335.9Mhz. In the BIOS, I always get a reading of 2.66Ghz.
Fluctuating voltage is normal. Speedstep (EIST in the board bios) changes the cpu voltage according to it's power draw to save energy. The multiplier is dropped to 6.0 at idle or when the cpu doesn't need all it's power. All designed to save energy. My i3 runs at 12 to 15 watts and the voltage drops to .972. Your readings are probably normal. If you don't want to save energy, try disabling eist and other energy settings in your bios.
As I said, this is normal. My cpu voltage ranges from .972 to 1.25. Your version of cpu-z may give realtime readings which is ok. Stop worrying if your system is running stable, or get a better power supply. Newegg has a corsair 650w for $59.99 after rebate in today's email promos. A great deal on a quality ps. The following issues are serious: windows bluescreens, random reboots, or system freeze-ups, which often indicate a heat problem. If you don't have any of these issues, I would leave your system alone.
If you don't want to see the changes, uninstall the cpu-z and try a different version of it, or disable all the energy saving features in the bios. There's nothing wrong with your system, unless your power supply readings are off. That's a completely different matter, but I doubt you have any problems. Stop worrying.