Actually, I gather that the very latest generation gives nVidia back their lead. But that in the previous generation ATI owned nVidia.
(Not to mention production problems, so nVidia had a hard to get series of cards that were both more expensive than and inferior to ATI's cards.)
Looking at the cards, I might have to get a new motherboard to get the most out of any upgrade to my video cards, which means a new CPU, which means pretty much a new computer....
My own fault, really - I scrimped on the motherboard last time, getting a model that was cheaper because it was being phased out. Faster SATA ports and some USB 3 connectors would be nice.
The Auld Grump
Mind you, it was $300 less than the last time I priced it out....