This happens alot when you are overclocking with a high baseclock. This one takes the cake though. Your motherboard is probably f***d up.
I have only bugged up to 5.5ghz, that was when i was running at 225 base clock though and 114 pci-e. Im surprised this happened at such a low base clock.
A few things to check:
Make sure all power saving options are disabled.
Make sure PCI-e frequency is manually set.
Make sure that the IOH PLL and CPU PLL arnt any higher than 1.8v.
Depending on your mobo, you also may want to try it out with Vdroop disabled.
Try it with c-state and turbo disabled as well.
What MOBO do you have?
I have an Asus P6X58D motherboard.
Xtreme Phase Full Power Mode: enabled
C1E, Speedstep, Turbo, Spread Spectrum: disabled
everything else set to auto
Is this an actual problem though, or just a bugged reading with my mobo? Like I said I've only noticed it in prime95 priority 10 for some reason. Also, it doesn't do it the whole time. It usually stays at 3990GHz but will jump up to some random number like that for a few seconds.