I wanted to give my stats:

GTX 580 using 331.82 drivers

Using Cudaminer 11/20/2013

Win 7 X64

options: -H 1 -l F16x14

Auto-tuning was using F32x8 which was averaging lower than what I am getting using F16x14.

avg about 230 khash/s

I was using the 64 bit version but I was only averaging about 200 khash/s

Using about 95% of GPU running at a temp of about 83 degrees Celsius.

I believe this is the best I can expect running a stock GTX 580 with no overclocking.