It SHOULDNT be the driver because I am currently using the 196.21 driver (NOT the defective 196.75 driver), but actually just updated yesterday from driver V186.  I updated BECAUSE of this problem I am having, which began while using that 186 version.  (I thought that maybe by updating the driver, it would fix the problem... but no luck)

As for the problem starting when the system starts up... what do you mean by 'system'?
OS, or Poser 8?
If you mean P8, then no, the problem isnt happening once P8 starts up.  It is happening while USING P8.  As soon as a GUI popup window comes up, and I click one of the GUI buttons (like OK, CANCEL, CONFORM), the program will suddenly stick on the screen without me being able to click ANYTHING.
If you mean the OS... well, this doesnt seem to be an OS problem because once P8 freezes, I can still operate my OS without any problems at all... except that P8 is stuck on the screen.  I can still open folders in Explorer, and run other programs too.  My memory usage isnt even increasing as if P8 is sucking all my memory trying to do something!!!!!! P8 just literally stops working.