Aargh. Lately I've been unable to stay in SL for very long. The client dies spontaneously, or it starts to use every available CPU cycle and grind down to maybe 4 fps if I'm lucky.
Today after a crash I saw a process running SLVoice chewing up almost all the cycles, so I turned off voice, but that proved not to be the problem.
Does inventory drag performance down? I really should delete a vast number of notecards from Fashion Consolidated and Fabulously Free.
UPDATE: I've updated to the nVidia 195.30 driver, which appears to help some, but the major improvement, for which I am greatly indebted to Laurana Newell, came when I cranked down the draw distance. (Makes sense, because we're talking O(n**3) here, right?) Silly me.