You should be able to archive your RT (or set up separate ones on a per character or per project basis) and cut its size down to a quarter of what you currently have. That will speed things up enormously because Poser reads the entire RT when it starts to build an image, and giving it 17 gigs to deal with is a bit much. I think the largest mine ever went was 3 gigs, and its rendering speed is just fine.

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