Search around the web for Softquadro instructions. The weird thing about the Geforce slowdown is that it's fairly unpredictable. Sometimes 3 windows, sometimes 1 assy and one model open. It's hard to say when the graphics buffer will choke. All Geforce's have this problem. Some notice, some don't. Softquadro or a real Quadro card are your only sure fixes. I read somewhere a couple months ago on a website (can't remember where) that someone was able to successfully Softquadro a Geforce FX board. Look around for that and be very diligent in the steps. Softquadro is a pain to get right but it does in fact work. If I can relocate the website I'll post it here.
I've found out a little more information on the Nvidia cards.
But first to clarify my problem.
It's not that the openGL graphics packs it in, so that rotating the model slows right down, this I can live with and have for the last year, I have to is close SW and restart it.
What is happening with my GeForce FX5700 is the graphics window and changes to hash or part of a previous model view or large blocks of various images (in my vulgar language shit). To recover I have to save and close blind then restart the computer. (at least 10 min).
I've discovered that the:
-GeForce FX5700 uses an new chip and it will only run on 5x.xx drivers. We spent half a day trying various 4x.xx drivers, only to find a comment on the Nvida forum (from a visitor) to say no 4x.xx driver work. I've tried all the drivers I can find 53.03, 53.04 and 53.06, the latter overcomes other problems, but no joy on my major issue.
-Rivatuner basically only works for driver up to 5x.xx
My supplier is kind enough to exchange my new FX5700 for an FX5600 or upgrade to the FX5900 which have been out for sometime and happily use 4x.xx and importantly can be modified with rivatuner etc.
When you consider the Geforce FX5900 at $490 Australian is the same as the Quadro FX3000 at $3300 Australian with some features unblocked, I have to say I feel I would be being ripped off. I have to choose the Geforce, at worst I may have to restart SW every couple of hours.
Hope this is of assistance to anybody looking at buying a new video card, and thanks for your comments