MaximumPC 2006 06

The Windows XP Hotfi x

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 affect-

ed by the bug, your scores will be all over the map.

Microsoft has released a hotfi x 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 specifi cally request the

hotfi x associated with issue “896256.” Luckily, it is available for down-

load at AMDzone.com. Just go to the website and search for “hot

fi x”. Once you’ve installed the fi x, you have to create a registry key to

enable it.

The Microsoft

hotfix is a regis-

try hack that up-

dates Windows

to work with

multiprocessor

systems.

The AMD Patch

AMD’s Athlon 64 X2 and dual-core FX-

series CPUs are indisputably the best

CPUs for PC gaming, but they don’t

always play nice with games. Gamers

are reporting a variety of problems, and

AMD has addressed these irregulari-

ties with a “dual-core processor driver”

update. It’s available at http://www.amd.

com/us-en/assets/content_type/utilities/

amdcpu.exe.

This driver update corrects several

issues by adding the line “/usepm-

timer” to the boot.ini fi le. This small

change allows both CPU cores to stay

synced at all times, which reportedly

fi xes most of

the issues we’ve

mentioned.

Intel does not

offer a similar

patch, but we’ve

heard reports

that adding the

/usepmtimer

line to the boot.

ini will also fi x

gaming issues on Intel machines.

To add it manually, right-click My

Computer and select Properties. Click

the Advanced tab, and select Startup

and Recovery. Click the edit button to

edit the boot.ini file. Append the last

line with /usepmtimer, save the file,

and reboot.

Adding one little line to the boot.ini file can help fix

irregularities on Intel and AMD dual-core systems.

DUAL-CORE SURVIVAL GUIDE

40 MA XIMUMPC JUNE 2006

For the past few months, readers have stuffed our Ask the Doctor mail-

box with emails complaining of bizarre game performance. And inevitably

we find that there’s a dual-core processor in the mix. We’ve experienced

problems ourselves in games—Beyond Good and Evil comes immediately

to mind. The problems can range from stuttering and choppiness to games

running at hyper speeds, and can occur sporadically.

Don’t fret: Both Microsoft and the hardware vendors have fixes for these

issues, and on the next two pages we’ll walk you through each of them, along

with two other scenarios that can help you troubleshoot a dual-core PC.

How to Fix Your Dual-Core Problems

Here’s how you do it:

1. Click Start, click Run, type regedit in
the Open box, and then click OK.
2. Right-click HKEY_LOCAL_MACHINE\
SYSTEM\CurrentControlSet\Control\
Session Manager, go to New, and then
select Key.
3. Type Throttle for the new key name.
4. Right-click Throttle, go to New, and
then select DWORD Value.
5. Type PerfEnablePackageIdle for the
value name.
6. Right-click PerfEnablePackageIdle, and
then choose Modify.
7. In the Edit DWORD Value box, type

1. In the Value data box, make sure that
   Hexadecimal is selected, and then click
   OK.
   8. Quit the registry editor.
   9. Reboot the machine and the hotfi x will
   be in effect.