I used to use Matrox cards all the time when I was building my own equipment. The main reason I built my own computers was 'cause it was a lot cheaper to do so, way back when. About the time Dell and Gateway were getting big, it became possible to get something ready made that met my needs without all the hassle, so I started buying whole machines.

Long about then, I started to notice that I had a lot of software that used OpenGL, and some research at the time led me to the conclusion that nVidia support was way ahead of ATI in that area. I don't know how much of that has changed, but I've used nVidia cards ever since, and I haven't had any trouble with them. Also, I keep thinking I'm going to play around with Gelato someday, so I feel like I'm keeping my hand in.

I don't know about Poser, present or future, in this regard, but I've seen a lot of Carrara users who've reported excellent results with an i7 CPU, getting 8 rendering threads that tool along at a very pleasant speed.