It looks like DriverMax is the only thing out there which can correctly identify which "Coprocessor" older AMD chipsets have and also which driver to download *and where to download it from*.

I didn't want to have to resort to such a driver utility. The last time I tried DriverMax on a PC it made such a mess of things with incompatible drivers.

But after finding quite a number of postings on various forums saying it worked, I downloaded it and sure enough it found the right driver and it works.