MBP 2.0Ghz Locked to 1.0Ghz When Running Without Battery ???

10-Dee-Q

macrumors 6502
Original poster
Hi i just discovered that my MBP 2.0Ghz is only runs in 1.0Ghz when running without battery plugged in!
i use Core Duo Temp to get the reading, and it won't move from 1.0Ghz no matter how big the load is, i tried to openned a lot of apps together and the CPU use percentage is at 90-100% but still it only run in 1.0Ghz

If i plugged in the battery the CPU will only run at minimum in 1.33Ghz depeending on loads, it can go to 2.0Ghz but can't dropped to 1.0Ghz even though the MBP is in idle and doing nothing,

is it something wrong with my MBP or others is the same ?
 

Josias

macrumors 68000
Mar 10, 2006
1,908
1
I dunno, but can you feel any difference? A cut in half would be significant, and anyone would be able to notice...
 

10-Dee-Q

macrumors 6502
Original poster
i dont really know wheter there is any differences or not,
or maybe just seeing the "1.0Ghz" reading in core duo temp just effect my mind that i see much more "beach ball" on my MBP :(

can anyone give any reads on yours MBP with core duo temp and without battery plugged in ?

thx.
 

GilGrissom

macrumors 65816
Mar 13, 2005
1,042
0
In system preferences go to Energy Saver and select the Battery option from the drop down list. Go to the Options tab and see what it says under "Processor Performance". By default when on batteries it is in "reduced" mode, so the battery lasts longer. Try setting it to highest if you want the absolute highest CPU performance constantly, or automatic for it to adapt more when needed.

Does this solve the problem your having?

I don't have a Core Duo so don't know how different the dual cores will act compared to a PB G4 1.5GHz.
 

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Pressure

macrumors 601
May 30, 2006
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Denmark
It's a known issue. It's actually a fail-safe built into the system.

Make a search in the Apple Support Forum to see that it is well documented.
 

Josias

macrumors 68000
Mar 10, 2006
1,908
1
Pressure said:
It's a known issue. It's actually a fail-safe built into the system.

Make a search in the Apple Support Forum to see that it is well documented.
Is this due to the new Intel architecture, or was it also an issue on the PB's?

Er det her på grund den nye Intel arkitektur, eller var det også et problem PowerBooks?
 

Pressure

macrumors 601
May 30, 2006
4,007
269
Denmark
Josias said:
Is this due to the new Intel architecture, or was it also an issue on the PB's?

Er det her på grund den nye Intel arkitektur, eller var det også et problem PowerBooks?
It's a safety feature.

There are several explanations. One is that the battery functions as a surge protector and takes any excess power and keeps the flow to the computer smooth. Removing the battery makes the processor especially vulnerable to power spikes, which can fry your computer and that could be the reason why it clocks itself down to 1.0Ghz.

The Intel Core Duo Processor and Intel Core Solo Processor on 65 nm Process Datasheet May 2006 also says this on page 86:

"With a properly designed and characterized thermal solution, it is anticipated that the TCC would only be activated for very short periods of time when running the most power intensive applications. The processor performance impact due to these brief periods of TCC activation is expected to be minor and hence not detectable. An under- designed thermal solution that is not able to prevent excessive activation of the TCC in the anticipated ambient environment may cause a noticeable performance loss, and may affect the long-term reliability of the processor. In addition, a thermal solution that is significantly under designed may not be capable of cooling the processor even when the TCC is active continuously."

On the next page it say the following:

"The TCC may also be activated via on-demand mode. If bit 4 of the ACPI Intel Thermal Monitor control register is written to a 1, the TCC will be activated immediately, independent of the processor temperature."

So removing the battery could tricker the TCC.
 

GilGrissom

macrumors 65816
Mar 13, 2005
1,042
0
QuarterSwede said:
I don't think he meant he removed the battery just unplugged the charging cord.
That's what I thought too...just unplugging the power cable.

Could the OP verify?
 

10-Dee-Q

macrumors 6502
Original poster
i did remove the battery and runs the MBP by power cable only
the reason is that i've been doing that since long time ago whne i use my previous windows notebook at home, i thought that it can save the battery lifetime a little bit, but i'm new to mac and don't know wheter is that the corrrect way or not.
for comparison, my Asus W1N uses Intel centrino Dothan 1,7Ghz and it can runs to 1,7Ghz without battery (only connected to power supply)
and my previous Acer Ferrrari uses AMD turion 64 2.0Ghz also runs from 1.0Ghz to 2.0Ghz depending on loads, i just don't get it why can;t i get that on my MBP, or maybe i should plugged in the battery all the time, but if i;m not on the move it will sort of shorten the battery life right?