During that time, I had a job for a major games company doing nothing but developing Windows graphics card drivers. They were moderately complex beasts (enormously complex compared to other device drivers), but not really that huge of a thing.

The biggest effort about them was reverse-engineering certain cards. The games often used very strange video settings, and the card manufacturers had poor, sometimes no, documentation about their operation at a low level.

Thanks for sharing. I'm surprised that game companies would do that. Is it the Voodoo era or slightly earlier (S3)? Does that mean you actually ship drivers with games? What did the card manufacturers say about this?