Now, here's the good part: Microsoft managed to preserve the NT 4.0 settings, so that they would have the same effect if applied to the bitmask of a Win2000/XP machine. In fact, the "old" values are still the default settings for this key! See for yourself and open the System Applet. If you have Win2000/XP Professional installed, it should already be set to Adjust for Programs. Now open the registry and browse to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\PriorityControl. (This is where we include the "standard" disclaimer that directly editing the registry—or even looking at it with Regedit.exe—may permanently damage your computer. Other side-effects include male pattern baldness, dry mouth, itchy scalp, recurring migraine headaches, and/or death.) Unless you've changed this previously, the value for Win32PrioritySeparation will be 2 (the old NT 4.0 setting). Now, switch back to the "Performance Options" window, tick the "Adjust for Background Services" option and click Apply. Switch back to the registry editor and hit F5 to refresh it. Now it's 24. This value of 24 has the same effect on processor scheduling as the NT 4.0 value of 0. Now use the GUI to switch it back to "Adjust for Programs" and click Apply. Back to regedit, F5 to refresh, and...tada! It's 38, which has the same effect as the NT 4.0 value of 2.
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