The Windows XP hotfix

While this may seem like old milk to some, it's valuable information.

"Windows XP has issues with dual-core processors' low-power states. For example, in WinXP, AMD's Cool 'N' Quiet technology automatically throttles the CPU, lowering its clock speed when the system doesn't need the extra power, but sometimes Windows won't crank the CPU speed back up when the system needs the extra juice. You can spot this problem by running a CPU-intensive benchmark - Folding@Home or Sisoft Sandra's CPU test, for instance - several times. If you're affected by the bug, your scores will be all over the map.
Microsoft has realeased a hotfix that corrects the problem, but here's the weird part: It isn't available as a download from Microsoft's website. You have to contact Microsoft and specifically request the hotfix associated with issue "896256." Luckily, it is available for download at AMDzone.com. Just go to the website and search for "hotfix". Once you've installed the fix, you have to create a registry key to enable it.

Here's how you do it:

Once you get the hotfix open regedit, then right click HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager, then go to new and select Key.

Next type Throttle for the new key name

Right-click Throttle, go to New, and then select DWORD Value.

Type PerfEnablePackageIdle for the value name.

Right Click PerfEnablePackageIdle, and then choose Modify.

In the Edit DWORD Value box, type 1. In the Value data box, make sure that Hexadecimal is selected, and then click OK.

Quit the registry editor.

Reboot the machine and the hotfix will be in effect."

Instructions courtesy of Maximum PC.

 

On the other thread (I presume that's why you've given this it's own thread, it said this hotfix is XP Home only, and not applicable to XP Pro?

 

That is the exact article, and this refers to XP in general. Although yes, the last post was about XP home.

 

Is there another way to check for this hotfix other than running a bunch of programs and monitoring the CPU usage?

 

It's not even CPU usage. It's just bringing the full speed of the CPU back up when it IS under full usage.

 

Here is the direct KB article. It mentions XP Pro. I'm wondering if this hotfix may effect battery life?

http://support.microsoft.com/?kbid=896256


PS - One thing not noted in this thread, You need to actually install the hotfx with the kernal update. The registry edit, is just to disable the hotfix.

 

Hmm, I downloaded a hotfix that has newer builds of the ntkrnl files than what MS has listed on the page linked above.