Your bus speed and multiplier are off. It should be at least 200MHz with a 16x multiplier.
It should be running in dual channel mode as it has four sticks of memory installed. They are differing speeds, so they will operate at the slowest memory speed of the DDR2 PC2-4300.
I saw this while surfing:
Could it be the Enhanced Intel Speed Step kicking in? Have you try to right click on desktop -> properties -> screen save -> power -> power scheme and select always on. Now is your P4 641 running at 3.2Ghz?
That is odd. CPU-Z is usually spot on. Do you have the latest version and can you post a screen shot of CPU-Z?
I just read this on the link I posted for you earlier:
Ensure Enhanced Intel SpeedStep technology is enabled in your BIOS. For Intel desktop boards the Intel SpeedStep technology option is under the, “Power,” tab and labeled, “EIST.” Ensure it is set to, “Enabled.”
If you have that option, see if you can disable it.