After installing Windows 7 I noticed that IO APIC was enabled. This is known to cause slowdown etc. I believe that it has been causing problems with my system (slow mouse response, window interaction, etc).
I was able to force it to be disabled on my guest and the system seems to be much more responsive at this point.
How to force IO APIC to disable after a Windows Install:
- Boot the Guest OS
- Go to Device Manager, and click on "Computers"~>
- Select the Properties of ACPI Uniprocessor PC ~>
- Click on the Driver tab, select Update Driver, ~>
- Click on the "Install from list or specific location"~>
- Click "don't search I will choose what driver to install" ~>
- In the window find and click on "Advanced Power and Configuration Interface (ACPI) PC" then click next ~>
- Click "finish" after Windows loads the new drivers. You may need your CD.(I didn't)~>
- Now click Close to exit those property pages, Windows will tell you to Reboot. DO NOT REBOOT! SHUTDOWN THE GUEST
Once the guest is shutdown you need to change the settings of the VM. Changing the IO APIC Setting within VirtualBox will not work. It keeps re-enabling the setting.
- Close VirtualBox and open your guest machine's XML configuration file in a text editor.
- Find the setting <IOAPIC enabled="true"/>
- Change value from "true" to "false"
- Save the file and exit the text editor
- Right-click on the XML file and open the properties.
- SET THE XML FILE TO READ ONLY (this will not allow Virtualbox to re-enable IO APIC)
- Start VirtualBox and Boot the guest OS
- After windows boots it should install some additional drivers and ask you to reboot again.
IO APIC should now be disabled
If you want to change any settings within VirtualBox you'll need to remove the read-only attribute from the Machine XML file.
Hopefully some will find this useful.