CPU Speed - why does it change?

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Not really an overclocking question but knowledgeable members might be able
to offer help :-)

I'm not too familiar with the workings of cpu...so I'd be glad for any
comments/advice ref the following.

Abit motherboard NF7-S and Athlon XP 2500 Barton cpu

Have just discovered I seem to be working with two different CPU speeds...

1.about 1830MHz when the sides of the computer are ON (the Barton's spec is
1883MHz so thats ok), and
2. about 1075-1095MHz when the sides are OFF

I had been under the impression ...clearly wrongly..that the speed of a
cpu under normal use was pretty well constant?
Made a note in Motherboard Monitor (MBM) of the cpu speed with sides of
the box OFF = 1094 MHz...with sides ON this jumps to 1796MHz !
Is that what could be expected, and if so how come?

And further...from start up and with sides off and cpu speed showing 1093MHz
and board
temp 29C and cpu temp 42C
I then put back on the sides, and, after 40mins temp rose to 36C and
48C but cpu speed still showing 1093!?
Then turned off the pc..then straight away turned on the pc and find temps
39 and 53 and cpu speed now up at 1829!!...does that make sense?

...and lastly Just checked the following when sides on and sides off via
with sides ON first (and sides OFF)

voltage - 1.648v (1.664)
Multiplier - 11 (11)
FSB - 166.4 MHz (99.5)
Bus Speed - 332.7 MHz (198.9)
Core speed - 1830 MHz (1094)

Again...does that seem reasonable?...Its baffled me :-)

Any help would be appreciated.

Re: CPU Speed - why does it change?

Something ain't kosher.Do you have the latest BIOS? All I can think of is
throttling,but I don't believe bartons have that feature. Or,spread spectrum
on steroids.Spread spectrum is only supposed to vary mhz by a small range.
What are you using to measure? And have you done benchmarks for both speeds?

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Re: CPU Speed - why does it change?

Sounds to me like Cool 'n Quiet is going funny, try turning it off in
your BIOS and see what happens...

John Smith wrote:
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Re: CPU Speed - why does it change?

The Barton hasnt got C'n'Q, i think its something like intrusion detection

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Re: CPU Speed - why does it change?

Measure with CPU-Z to see if you get same results

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