P5 firefly chokes for a few reasons which are rather hard to pin down. I have, for example, rendered dozens of scenes (ok like 6) right in a row of one v2 and 6 m2s all in the same scene with props and sets and not have a lock using FF and ray traced shadows. I do the samething with 2 or 3 v2s and it croaks. I've also had the same scene that rendered on my 2.5 AMD barton with 1.5g ram not render on an older 2.4 amd with 1.25 g of ram. Here are a few things I noticed: 1. The more MTs on a figure, the worse firefly works. 2. Magnets may have an effect. 3. Ray tracing of huge, detailed scenes for ray traced shadows can cause locks. 4. Textures can fill ram since Poser does not ditch textures its not using. Now do you lock up on an actual render part way through or do you lock at the "add Objects" stage?