Thanks kawecki, for all the info. I pretty much knew what it was doing, 'casue I read as much as I could before doing anything at all.
temperature is not a problem, because the RivaTune program has a setting in it to adjust the fan speed on the card itself, to cause it to run faster, longer, at certain temperatures - all kinds of possibilities. Plus, I have another program which constantly monitors CPU and inner case temperatures (HD temperatures as well), and that display is always up where I can see it. I have a 3.2 ghz Pentium and it never goes above 45C. The case temp never goes above 44C, and the Nvidia software shows the vid card temp at all times too. An hour of Oblivion with everything set at max made a temp of 56C in the card.

*"*In MikeJ's case it seems like the OpenGL functionality on his card can't handle the increased clock speed. "

Not true. I had both the memory speed and the core clock up 25%, playing Oblivion, running Lightwave, and twisting and spinning hi-res texture models around in Deep Exploration, all with no problems at all. Nice speed increase, no problems at all, no instability as far as I saw in a few hours of messing around and rendering.

It was only Poser 7 that had a problem with it, and I tried it with Poser 6, too, also with no problem.
They did do some mucking around with Poser's OGL in Poser 7, which is what leads me to believe somethin' ain't right there.