I just had a look at you Pit Test Link
Most looks real good
These "unnecessary" processes are "trivial" but can be disabled:
Java Platform SE 6 U11 Sun Microsystems, Inc. C:\Program Files\Java\jre6\bin\jusched.exe
Java Platform SE 6 U11 Sun Microsystems, Inc. C:\Program Files\Java\jre6\bin\jqs.exe
Intel® Common User Interface Intel Corporation C:\WINDOWS\system32\hkcmd.exe
Intel® Common User Interface Intel Corporation C:\WINDOWS\system32\igfxpers.exe
Windows Live Communications Platform Microsoft Corporation C:\Program Files\Windows Live\Contacts\wlcomm.exe
Windows Live Mail Microsoft Corporation C:\Program Files\Windows Live\Mail\wlmail.exe
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There are no Driver Update Alerts
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The "Most Problematic" indicator in the entire Results is:
Internet Explorer settings for the Restricted Sites security zone -- Should be set to "High"
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You can perform the Registry Edit to Create an optimized TcpWindowSize D-word item
The instructions are very well described in your Pit Test Results.
**Be sure to backup your Registry before making changes
Benefit of optimizing you internet connection TcpWindowSize is probably "negligible" and will not improve other/overall machine performance.
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Let's circle back to what it is that is causing you concern.
For instance, I believe that you opened this topic with Concern about BSOD Error Screens.
What is the current situation of your machine performance?