Thanks for the reply. I've got a brand new board, the fan didn't spin at
all, until I noticed a transistor that had one pin not soldered (near the
fan connector, on the reverse side). It seems ok now. And these boards
aren't cheap, you'd think they'd test them better!
unless you want to roast some marshmellows over an open graphics
card I would say yes. Nvidia cards generate a large amount of heat
and I would suspect it would have problems after a few minutes.