I have both, the current is a Pentium 4, 3.2 GHz and the one before was an Athlon AMD XP 2000, 1.6 GHz. Poser runs fine on both and I like both. Only problem I had was that the Athlon got very hot while rendering and sometimes rebooted when the CPU got too hot above 70C. I opened the case and placed a fan there to cool it down and that helped a bit. The P4 runs at 33.4C and only goes up to max 45C when I render a large image, but I guess that is because of the Thermaltake case with 7 fans ;-).

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