After drawing a quad with cullmode != none, the r500's Windows driver's
ability to clip clear rectangles to the viewport is permanently broken.
This shows up as a test failure in depth_buffer_test().

It doesn't in ddraw2 and 7.

R200 creates P8 3DDEVICE surfaces in video memory, and consequently
returns a different error message when trying to create a device.

user32: Create the desktop window to trigger builtin class registration before accessing the class list.