The following is a list of some performance KB updates for Windows 7 SP1 & Windows Server 2008 R2 SP1 that are not available through Windows Updates.
For some reason, these updates must be requested by email from Microsoft.
All patches and updates below are for x64 architecture. If you need x86, please request the file from Microsoft.

KB2675785
Fix: Slow data transfer speed in Windows 7 or in Windows Server 2008 R2
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KB2869302
Fix: Slow-link transitions fail in Windows 7 SP1 or Windows Server 2008 R2 SP1
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KB2778834
File becomes corrupted when you try to overwrite the file while it is opened by another user on a computer that is running Windows 7 or Windows Server 2008 R2
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KB2775511
An enterprise hotfix rollup is available for Windows 7 SP1 and Windows Server 2008 R2 SP1 and contains 90 specific hotfixes.
After this update is installed, you must install update KB2732673 & KB2728738 found below to fix a regression issue in the Rdbss.sys file and Profsvc.dll file. To do this, install updates:
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KB2732673 (Install this after KB2775511)
"Delayed write failed" error message when .pst files are stored on a network file server that is running Windows Server 2008 R2
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KB2728738 (Install this after KB2775511)
You experience a long logon time when you try to log on to a Windows 7-based or a Windows Server 2008 R2-based client computer that uses roaming profiles
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