Tag Archives: “Hard Disk Drive”

Windows Server 2008 R2 and SBS 2011 RTM or SP1 – You may experience disk I/O performance issues with certain Intel Xeon Processors

You may experience disk I/O performance issues if your server contains an Intel Xeon Westmere-EX (10 Core) processor

This can occur because some of the I/O completion port objects are not cache-aligned. This behavior is what causes poor disk I/O performance.

You can resolve the issue by updating Ntoskrnl.exe and Ntkrnlpa.exe updated versions are available for download from http://support.microsoft.com/kb/2545635

Microsoft Windows Vista – SP1 or SP2 and Microsoft Windows Server 2008 – SP1 or SP2 – How to Easily Free Up Some Disk Space

Have you started to notice that C drive is getting a little full or do you just want to have a spring clean, well you may not realise it but when you installed Service Pack 1 or Service Pack 2 onto your Windows Vista or Windows 2008 Server that Microsoft very sensibly backed up all the old system file before replacing them with new ones.

Assuming that you have had Service Pack 1 or Service Pack 2 installed for sometime without issue it may be good to know that you might be able to reclaim some disk space by dumping these obsolete system files.

Simply launch an elevated Command Prompt by right clicking “Command Prompt” and selecting “Run as administrator”.  Once you are in a command prompt simply paste in the following according to the Service Pack you are currently running:

Service Pack 1 you need to paste: VSP1CLN.EXE

Service Pack 2 you need to paste: Compcln.exe

Be patient with these commands they will need time to enumerate a large number of files and could take up to 60 minutes to complete.  Once finished I would recommend a reboot.

With these commands we are telling the operating system to remove any of the superseded service pack files.  If you do not have any files to remove it might be because someone else has already removed them or your computer/server may have already come with Service Pack 1 or Service Pack 2 pre-installed/integrated.

Improve Windows Performance by Enabling SATA AHCI Mode

Probably the biggest bottleneck in most computers these days is the hard disk drive and its interface (SATA).  Depending on the current configuration of your system it may be possible to further improve performance by turning on SATA AHCI mode in your system BIOS and ensuring that your Operating System has support for AHCI enabled.

Here is a brief guide to verify if AHCI is already enabled and if not to ensure that AHCI can be enabled and will work correctly.

Restart your computer and wait for the BIOS Screen to appear, you will need to enter your BIOS Setup Screen.  The Key to enter the BIOS Screen can vary between systems,  “Delete”, “F1”, “F2” or “F10” are some of the most common shortcuts.

Once in the BIOS Screen locate the SATA Controller options and check if the SATA mode is “AHCI”, “Compatible” or “IDE”. The “Compatible” and “IDE” options are usually selected when you are using a Legacy Operating System that does not have native AHCI and/or SATA support.  The trade off with these modes is that the operating system is unlikely to be able to take full advantage of all the features of your SATA Hard Disk to improve system performance.

If you find that your system is set to “Compatible” or “IDE” mode then don’t change anything just yet.  First we need to make sure that your Windows Operating System has AHCI support installed and active so lets exit the BIOS without making any changes and boot back into Windows.

Once you are back in Windows click on the “Start Menu” and then in the “Run” or “Search” box you need to type “regedit.exe”

You will need to locate the following two registry keys


Under both of the listed registry keys above you will find multiple values, amongst these you will find a “REG_DWORD” value called “Start” and these both need to be changed from “0” to “1” to tell Windows that we want these additional AHCI controller drivers to be loaded at startup.

You may ask yourself why these are not enabled by default, Windows actually disables any unused drivers to speed up the Windows Startup process.  In this instance we just need to turn these two back on to accomplish our ultimate goal.

Now that we have AHCI support enabled within Windows lets reboot the computer once for these Registry changes to take full effect and to give Windows a chance to initialise the AHCI drivers.

The final set of this process is to restart the computer one last time and enter the BIOS screen again by using the process above.  Once in the BIOS locate the SATA Controller options and change the SATA mode to “AHCI”.  Remember to select “Save Changes and Exit” so that everything takes effect.

You should now find that the system boots back into Windows, the first boot may be a little slower than usual while the operating system re-detects your Hard Disk Drive.  Subsequent startups should be significantly faster.

If you have any issues booting back into Windows after making the switch to “AHCI” then simply go back to the BIOS and revert your SATA mode to its previous state and you will find Windows boots as before.