Window 7 Paravirtual SCSI (PVSCSI) on ESX 4.1

Well, over the weekend, I got a chance to convert from using XP Professional for my “Windows” needs to Windows 7. When I created the Windows 7 system Virtual Machine [VM] on ESX 4.1 with update 1, I used the defaulted “LSI Logic SAS”. This has been the “Controller of choice” for many a Windows 7 or Windows 2003/2008 install. I wanted to use the new VMware Paravirtual scsi driver, it’s faster and more lightweight on the Windows 7 VM. Do verify that your VM’s operating system will support this and your version of ESX/ESXi will support Paravirtual SCSI by visiting


Here’s how to convert from “LSI Logic SAS” to “VMware Paravirtual” in a nutshell:


1) Build your Windows 7 VM system with the “LSI Logic SAS”. Install all drivers and install VMware tools.

2) Shutdown the Windows 7 VM.

3) Edit the properties of the VM.

4) Click on the [ADD] button.

5) Add a “Hard Drive”. Select “Create a new virtual disk”. Select a small size, like under 2Gb. The critical piece is under “Advanced Options”. You must select the Virtual Device Node as a different front number, example: SCSI(3,0) where the 3 is different than your current SCSI disk drive. This tells VMware that your connecting an ADDITIONAL SCSI controller [thus, the trick to get VMware to ask what kind].

6) You will now see in bold that you have a new hard drive and new SCSI Controller [if you picked 3:0, you should see “SCSI controller 3” in your hardware list]. Click on new controller, and then click on [Change Type…] in the upper right corner.

7) Change the type to “VMware Paravirtual”.

8.) Boot your Windows 7 VM.


When Windows 7 boots, it will go through the steps of adding the driver for the VMware Paravirtual SCSI [PVscsi driver]. Once Windows 7 has completed this, you can shutdown the Windows 7 VM by telling Windows 7 to “shutdown” from inside the VM.


Are we there yet??? Well, almost… The Magic Kingdom is now in sight and were on the right track to get there.


With the Windows 7 VM shutdown, remove the temporary drive we added [it was on SCSI 3:0 if we recall], now click on the “SCSI Controller 0”, the default controller for Windows 7. You can now change the type by clicking on [Change Type…] and select “VMware Paravirtual”. Since Windows 7 already installed the controller, it knows about the controller, and can boot from. Restart your Windows 7 system and your now running on the newly installed [and faster] VMware Paravirtual driver.


How cool is that?