They may not be WHQL certified, per Wikipedia:

> A company can choose to sign their own drivers rather than go through the WHQL testing process. These drivers would not qualify for the "Certified for Windows" logos, but they would install on 64-bit versions of Windows and install without a warning message on 32-bit versions of Windows Vista or Windows 7. However, it will not install without a warning message on Windows XP.

If they are, I don't know enough about how rigorous Microsoft's certification process is now to comment. It used to be just looking for things that would cause kernel instability but it seems the standards have increase a lot since its exception.

But they are pushed through Windows Update? Doesn't everything there have to be WHQL?

Correct. To use the non-MSFT signed approach, the driver has to add the cert to the registry beforehand somehow (eg. using certutil -addstore -f TrustedPublisher), which obviously rules out a straight install using Windows Update.

I would be surprised if WHQL tested drivers on counterfeit hardware.