Seems the test buttons have been removed.
When I run DXDIAG and go to the video tab, there are no "test" buttons for "Test DirectDraw" or "Test Direct3D" etc. The collumn on the left shows them all enabled, but the lack of test buttons makes me wonder if hardware support is somehow disabled. I just upgraded from a ATI Radeon 4350 card (these dxdiag buttons were missing then) to an NVIDIA GTs 250 card. PCI-E x16 enabled in bios.
The card works, drivers loaded and there is nothing 'suspect' about my video performance - only the lack of these buttons in dxdiag which have been there for as long as I can remember.

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