I have an HP Slate 500, which has the GMA 500 graphics processing. The tablet comes with driver version 22.214.171.1245. When you physically turn the tablet 90 degrees, the desktop rotates accordingly. I don't want this to happen. On this tablet, you can push the power button to a locked position to disable automatic rotation, but I want to accomplish this via software instead.
Googling the topic led me to discussion of an "Enable Rotation" option. The "Graphics Properties" window for the above driver version does not have that option. So, I installed the latest (???) version on Intel's website... 126.96.36.1990 (yes, it seems like it would be an older version???). This does have that option. I set it to OFF, to hopefully disable automatic... but it doesn't do anything. When I physically turn the tablet, the desktop still rotates.
How to accomplish this?
Have you considered contacting your computer manufacturer? Rotation mode is a feature controlled by the VBIOS of the graphics controller, this can be customized according to your computer specifications, and this means that only your computer manufacturer can modify this feature through Vbios, also, try getting drivers directly from your manufacturer.