Specifically on the 64-bit OS issue:

If anyone is considering upgrading to a 64-bit OS, I'd go for Vista64 rather than XP64, as drivers and so on are being developed specifically for the former.

I installed Vista64, dual-booted with XP Pro (i.e. 32-bit) about 8 months ago. At first Vista64 was practically unusable due to lack of drivers and all manner of annoying glitches. Needless to say, I spent most of my time in XP, quietly fuming that I couldn't use all the lovely RAM I'd bought.

Since then I've booted in Vista64 once a week or so to keep it up to date. In the last month, after installing Vista SP1 and following some of the recommendations made here: http://www.pcstats.com/articleview.cfm?articleID=2238
I can now spend 99.5% of my time in Vista64; maybe once a week I have to hop back into XP for something.

Now that it finally works properly it's fast, stable and uses all 8Gb of installed RAM.

I've no intention of getting PoserPro, but I'd guess that it's been developed using Vista64 rather than XP64.

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Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)

PoserPro 11 - Units: Metres

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