Yes, Poser / Pro / 2010 works fine with most current gaming graphic cards. But you mentioned other 3D software will run on that Dell also.
Check Tomshardware:
www.tomshardware.com/charts/workstation-graphics-charts/benchmarks,3.html
More or less all relevant workstation cards are there for you to be compared.

One thing that Tomshardware mentioned in a test (www.tomshardware.com/reviews/amd-firepro-v8700,2154-10.html) was that even though the workstation cards like the ATI FirePro are technical nearly identical to their gaming sisters the drivers are another story.

Tomshardware wrote:
"As you can clearly see, the ATI driver programmers have done an amazing job. The two models' hardware is 99% identical, and yet the FirePro adapter completely outclasses the cheaper Radeon gaming card. The most extreme case in point is Maya, where the FirePro V8700 is six times faster than the Radeon HD 4870"