Thanks, Sniper297!
Come to think of it, you're right!
The "history" (size of data retained) of the patrol - must have been why I was getting artifacts (like a billowing smoke trail from my last "kil") which followed my sub everywhere I went after 2-4 'refits' - rather than some NVidia "stuff" from inferior drivers. I haven't seen it recently (patrols limited to 2-3 refits), so thought it was 'fixed.'
I thought it was corrected with my 'new' drivers (using a 640M on my Dell XP One 2710 system [i7, 3.3, 8G mem, Win7 64-bit] with 3.31 or 3.34 drivers, for my embedded video).
Thanks for the heads-up!
Good Hunting!