Not sure what it is, but could be that the graphic card is not support correctly by Poser, since it just shows a black screen, the library might be slow as well, if it have issues showing the thumbnails.

Can you see the graphic card in the render settings? meaning can you select it there?

Alternatively, which is a bit more technical. But if you have a none onboard graphic card from your old computer you can try to install that in the new one if it fits and see if that works.