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Alex Granovsky
gran@classic.chem.msu.su

Running Firefly under Windows 7 (Win2K8 R2) on computers that
are overclocked using FSB frequency settings rather than CPU multiplier,
one can encounter the problem when the Wall clock time as reported by
Firefly is incorrect; and hence, CPU utilization is underestimated by
program. This is caused by a combination of some incorrect assumptions
made by CPU itself and by Windows 7 when running on overclocked systems.
More precisely, some motherboards/BIOSes dynamically varies the FSB
frequency depending on the processor's load, and this results in TSC
(Time Stamp Counter, the internal processors' clocks) not being longer
the reliable source of time, even if processor claims it is; and some
of Windows timer-related API becomes broken as the sequence.

Actually, this does not cause any real performance degradation,
however, just looking into outputs one can easily suppose that
there is serious performance degradation as compared e.g. with
Vista.

The workaround is to execute the following command in the
Administrator's command prompt window, and then reboot your system:

 bcdedit /set USEPLATFORMCLOCK TRUE 

This must be done only once.

Our thanks to MS guys who suggested the workaround.

And finally, the word of advice is - do not overclock (DNO)!

Regards,
Alex Granovsky