My first operation would be to check the memory. If you just installed a 256M module, it may be incompatible with the memory you have in there. Depending on the motherboard and processor and chip set, in some computers, new memory has to exactly match installed memory. That would be the first thing I would check. The CPU could have gone bad, but if it had you would have noticed problems in your other programs as well, or it would simply not function. I know nothing about Macs, so I can't really go any further than that. But basically it sounds as if the memory is incompatible or faulty. Your graphics card wouldn't affect render time. Render all takes place in CPU, floating point processor and memory, and it loops in the temp file of your hard drive, at least that's where Bryce puts it's loop file.

Talent is God's gift to you. Using it is your gift to God.