found a good launch config on the ACX 750ti: -l T15x1. With n-factor 16, I get ~ 310 H/s with tpruvot's miner. Tried same settings with sp_'s and it errors out.
[2015-10-17 05:30:33] GPU #2: Err 77: an illegal memory access was encountered (salsa_kernel.cu:870)
[2015-10-17 05:30:33] GPU #2: CUDA error `an illegal memory access was encountered` while executing the kernel.
[2015-10-17 05:30:33] GPU #2: cudaError 77 (an illegal memory access was encountered) calling 'cudaMemcpyToSymbol(pdata, host_pdata, 20*sizeof(uint32_t), 0, cudaMemcpyHostToDevice)' (keccak.cu line 471)
[2015-10-17 05:30:33] GPU #0: CUDA error `an illegal memory access was encountered` while executing the kernel.
[2015-10-17 05:30:33] GPU #1: CUDA error `an illegal memory access was encountered` while executing the kernel.
[2015-10-17 05:30:33] GPU #0: cudaError 77 (an illegal memory access was encountered) calling 'cudaMemcpyToSymbol(pdata, host_pdata, 20*sizeof(uint32_t), 0, cudaMemcpyHostToDevice)' (keccak.cu line 471)
[2015-10-17 05:30:33] GPU #0: Err 77: an illegal memory access was encountered (salsa_kernel.cu:870)
[2015-10-17 05:30:33] GPU #2: Err 77: an illegal memory access was encountered (salsa_kernel.cu:870)
[2015-10-17 05:30:33] GPU #2: CUDA error `an illegal memory access was encountered` while executing the kernel.
[2015-10-17 05:30:33] GPU #2: cudaError 77 (an illegal memory access was encountered) calling 'cudaMemcpyToSymbol(pdata, host_pdata, 20*sizeof(uint32_t), 0, cudaMemcpyHostToDevice)' (keccak.cu line 471)
[2015-10-17 05:30:33] GPU #2: Err 77: an illegal memory access was encountered (salsa_kernel.cu:870)
[2015-10-17 05:30:33] GPU #2: CUDA error `an illegal memory access was encountered` while executing the kernel.
[2015-10-17 05:30:33] GPU #2: cudaError 77 (an illegal memory access was encountered) calling 'cudaMemcpyToSymbol(pdata, host_pdata, 20*sizeof(uint32_t), 0, cudaMemcpyHostToDevice)' (keccak.cu line 471)