Here's the result when I use autotune...
[2014-02-27 15:57:33] GPU #3: cudaError 6 (the launch timed out and was terminat
ed) calling 'cudaDeviceSynchronize()' (D:/Christian/Documents/Visual Studio 2010
/Projects/CudaMiner/salsa_kernel.cu line 644)
"launch timed out" is unusual for autotuning an scrypt coin.
use -l T14x24 instead of -l T14x32. This should fit your cards.
the problem arose when you updated your cudaminer release from a December 2013 to a February 2014 release. Kernels were swapped out (nVidia's submission proved to be a bit faster than David Andersen's kernels).