If you see the adapter listed as Microsoft Basic Display Adapter or Standard VGA adapter, then it means that Windows is working with the pre-loaded generic and basic video drivers.

The Microsoft Basic Display Adapter is software that’s built into Windows that provides display and graphics capabilities when software from your hardware manufacturer isn’t installed.

I just updated to build 10565 and now I can only use Microsoft Basic Display Driver for the display, so I'm stuck at 1280x1024 at best. My Radeon HD 3850 is listed under Display adapters in Device ...

This will open Device Manager window. At Device Manager window, click Display Adapters to expand it. Right click on your graphics card driver and then click Uninstall from the drop down menu.