Hi!
I've built a new machine with an ASUS P5N32-E SLI PLUS motherboard,
equipped with an Intel(R) Core(TM)2 Quad CPU. The system seems stable
and well-performing. However, I'm curious about the following:
In the BIOS settings, there is an "Enhanced Intel SpeedStep (TM)" item,
which can be disabled or enabled. I've tried to hook a cpufreq module on it
but it seems to be unsuccessful. Neither speedstep nor acpi-cpufreq modules
are recognizing the hardware, so the feature seems unsupported.
However, when the BIOS SpeedStep setting is enabled, strange things happen.
In /proc/cpuinfo, the CPU frequency is always reported as 900 MHz (while
normally it's 2.6GHz), but the bogomips value is at 5220, which corelates
with the standard 2.6G clock. Also the system performance is not so low as
for 900M clock - I can see a small slowdown, but it may be about 5%, not more.
Even with an artificial load of all cores (4 cpu-eating tasks run concurrently)
the frequency reported by /proc/cpuinfo is at 900 MHz and doesn't never
increase.
So what does it mean ? Is the SpeedStep feature usable just by setting the
BIOS ? Isn't it limiting the performance too much ? Why the clock always seems
to be low ? I'm keeping it off until I know all the answers :-).
I'm attaching my DSDT for reference.
With regards,
Pavel Troller
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