Wierd throttling problem

First, a quick question: How can I disable windows XP (sp3) power management entirely? XP downclocks me to 50% CPU max when on battery power, and that's really not ok with me.

Second, with RMClock (I'm working on undervolting my CPU), the moment I enable P-State Transitions on a profile, then select that profile, my CPU gets throttled 4% down from it's clock speed. Thus, when running at 2.7ghz clock, I'm getting a 2.6ghz throttled speed. This 4% throttle remains even if I disable pstate transitions, select a different profile, exit RMClock, or anything else.

Occassionally, opening Windows' Power Management control panel app and selecting another power profile corrects this, but not very often. Most frequently, I need to reboot to remove that 4% throttle.

Interestingly, if I unplug my laptop in this state, XP downclocks the CPU to 1.35ghz, then throttles it 4% further down from that.

I've been testing with and without Orthos running, to be sure of maximum CPU utilization.

With that 4% in place, I'm getting 96% CPU utilization and 100% OS utilization reported whenever the CPU is stressed.

It's rather frusterating =/

 

1. power settings are under control panel -> power options

2. The cpu will run at 50-60% when not under load but throttles up to 100% when the horsepower is needed. This caused me a great deal of stress when I first got my 9260 because my desktop was an older p4 3g and runs at 100% all the time. It's normal and you should not worry about it. You will have the gz when you need it. I spent a lot of time checking into this. Now I'm confortable that it works as it is supposed to.

3. Until I fully understood the throtting thing I tried to force my e6700 to run at full speed all the time too in the beginning and noticed the same thing you describe. Change it and I couldn't get it to change back. However after rebooting ( or maybe it was power-cycling) it reverted back. The cpu setup is done by the clevo bios and can't be changed permanently which is why those who overclock these notebooks run the "tools" for tweaking all the time instead of jst setting it and forgetting it.

4. There is a relationship between the voltage and the speed (GHZ). If you under-volt enough you will reduce the min / max voltage settings the bios sets and not get the full cpu capability. I doubt you will increase the life of the chip by doing that. The thing that reduces the chip life the most is HEAT. Keep it cool instead of under-volting BUT that's just my opinion...

 

I agree with you that heat is what really wears on CPUs. However, wouldn't under-volting also help with cooling? Thus prolonging the life of your CPU?

 

Ok, got everything worked out. As to my first problem - Windows would lock my CPU under battery to 50%, regardless of system load. All numbers obtained in my first post where done with Orthos running my cpu full out to be sure I'm getting max speeds. I've been unable to find a place in windows where I can manage CPU throttling like that while under battery power - Power Options only gives me the ability to set times for idle component shutdown, not lower level things such as processor throttling/multipliers.

It turns out my system was "sticking" at 96% with RMClock because the T9300 uses a 12.5x multiplier, and RMClock deals only in whole numbers for multipliers. So, I had to enable IDA (which runs at 13x, though it never actually turns on) to allow the system to ramp up to 100% (that is, 12.5x). Curious, but it works.

With RMClock managing my power settings, I've been able to prevent the throttling while on battery power. It's nice to know if I need the power, I'll get it, rather than having to slog along under 50% CPU power all the time I'm on battery.


All that said, I'm curious. Is there somewhere in Windows where you can edit all the details of the windows power profiles? Clearly, the encompass more than just when to turn off your screen/hd/pc, but I'm just not finding the options to do it. It's not needed anymore, as RMClock is handling everything nicely, but it's mostly a point of curiousity.

 

I believe you are correct on that one. It should theoretically run cooler.

The Power settings are stored in the registry.
in a command window (start-run cmd.exe) you can get to some settings that aren't available in the control panel applet using the command

powercfg
[edit 7:02pm 6/10/2008 Just discovered my doc on this I think the command you might want is powercfg /processor-throttle-dc NONE ]

Don't be surprised though if you cannot get it to shut off perm though because the clevo bios comes into play too.
gl