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enaslund · Aug 4, 2006, 07:37 AM

I have noticed that while using windows on my MacBook, that the processor performance is 'turned-down' while running on battery. This is noticable during full screen video playback, choppy frame rates and choppy sound. Even just moving windows around the desktop is choppy.

When plugged in, it runs great.

I know in OS X there is an option to throttle the processors performance based on power source, but I am not able to find this option in Windows. Thanks in advance for any assistance.

ghporter · Aug 4, 2006, 11:24 AM

Throtling the processor speed is normal behavior for Windows. It's to help preserve battery life because the machine knows when it's plugged in and when it's on battery. It sounds like it's being overzealous in your machine.

Now the good news: if you want to run the machine at full speed all the time you can change the power saver settings through the Control Panel. Select Control Panel|Performance and Maintenance|Power Options, and choose one of the preset power profiles, such as "Desktop." That should tell the OS to ignore when it's on battery. Of course you won't get nearly the same battery life that way...

subvertbeats · Aug 17, 2006, 12:58 PM

Originally Posted by ghporter

Throtling the processor speed is normal behavior for Windows. It's to help preserve battery life because the machine knows when it's plugged in and when it's on battery. It sounds like it's being overzealous in your machine.

Now the good news: if you want to run the machine at full speed all the time you can change the power saver settings through the Control Panel. Select Control Panel|Performance and Maintenance|Power Options, and choose one of the preset power profiles, such as "Desktop." That should tell the OS to ignore when it's on battery. Of course you won't get nearly the same battery life that way...

Unfortunately thats not the case.

The issue still occurs.
Even when forcing the processor to run at its full multiplier using NHC, the issue STILL occurs.

The only way to fix the issue is to:

- In Device Manager, expand the batteries tab and right click and disable both the ac driver and the battery driver

- Restart.

Unfortunately, you lose the battery meter, but I was unable the use my SlingPlayer without the AC plugged in, a necessity for me.

So until I find a better solution I live without the batery meter,

Hope this helps someone.

ghporter · Aug 17, 2006, 01:18 PM

That's not typical Windows behavior, and I have to think that it's due to the hardware drivers Boot Camp provides. On the other hand, they just released version 1.1 of Boot Camp and reports indicate that a lot of things have been fixed.

I'm quite interested in whether this changes your experience, subvertbeats.

subvertbeats · Aug 18, 2006, 05:33 AM

Hi Glenn

Unfortunately not, same behaviour. I had hoped it would resolve it

I think that you are correct, it does seem to be the battery drivers at fault.

However, they are MS drivers; not supplied with Bootcamp to the best of my knowledge:

ghporter · Aug 18, 2006, 06:47 AM

That's definitely a "lack of working driver" issue. Have you tried reloading the drivers? In Device Manager, double click on the "Xed" device, click on the Driver tab and then the Update Driver button. You'll have plenty of options, but I'd go with allowing Windows to connect to the Internet and installing the software automatically to start.

Windows is supposed to manage power by telling the hardware what to do and when. If it is not running at full speed even when plugged in, there's a problem somewhere, and I'm thinking it's the power system drivers. Restoring them-from something other than the original installation-might help.

subvertbeats · Aug 18, 2006, 09:32 AM

Hi Glenn

No, you've got the wrong end of the stick there.

I manually disabled those drivers (hence the red X) as its the only way I can stop this issue happening.

With the drivers enabled, when running on batteries, I get dropped frames and glitchy audio especially wehn running full screen. This is with DVD's, AVI's and most commonly my SlingPlayer (slinging live TV from my PVR).

I just showed that graphic to show that they are MS drivers, not Apple / Bootcamp drivers.

To clarify, before my 'disabled driver solution' everything worked perfectly with power connected, disconnect power and problems started. Assumed it was to do with speedstep etc, so used utilities and settings to keep the machine running at full speed, even running on batteries. No change, the problems remained. The only solution I found was to disable those drivers. Now everything works great when running on batteries, but I have no idea when the machine will run out of charge and sleep.

Strangely, a friend with a non Mac laptop has noticed a similar phenomenon:

Strangely enough - I have been having a problem with my Laptop that it just drops out and I have to reconnect slingplayer.. which was very annoying - i have just realised that it doesn't do it with power attached!!

So must be a general problem with power saving functionality! I have Intel Pro 2200BG built in adaptor.. gonna try the suggestion and see if it fixes my prob to... :-)

(From the slingcommunity.com forums)

subvertbeats · Aug 20, 2006, 05:38 AM

Surely others are seeing this ?? You may not notice it in general use....

ghporter · Aug 20, 2006, 10:33 AM

Originally Posted by subvertbeats

Hi Glenn

No, you've got the wrong end of the stick there....

Oops. A careful reread of your posts (all of 'em) makes it clear that I jumped to the wrong conclusion.

It's still NOT normal behavior-especially for Microsoft's own drivers. And there hasn't been a ton of other reports of this either.

When MY MBP shows up (still don't know when it'll ship, as it's being procured for me by a third party), I'll of course delve into this myself...

subvertbeats · Aug 22, 2006, 07:46 AM

Thanks Glenn,

FYI the OP here, and myself both have MB's not MBP's

Ben

ghporter · Aug 22, 2006, 10:38 AM

I had that down-I just wanted to point out that I don't yet have an Intel Mac to play with. Since the third party hasn't told me yet when to expect delivery, I'm getting a little antsy about it.

Anyway, if there's a difference in behavior between MBs and MBPs that would add a whole new level to this weirdness. Let's see if anyone else posts about this issue and glean what we can about it from their experiences.

subvertbeats · Aug 29, 2006, 06:29 AM

Cheers Glenn, appreciate your help

licht · Nov 8, 2006, 02:58 AM

same problem here and i think it's a huge problem, I tried your solution (disable a couple of drivers) and it works. Any other solutions would be appreciated.