I'm getting very strange performance with both kernels.

My command line is:
phoenix.exe -u http://loginsauce@sauce.net:8332 -k phatk DEVICE=0 VECTORS BFI_INT FASTLOOP=false AGRESSION=12 WORKSIZE=128

and I'm getting exactly, with no variation, 67.28 Mhash/s on a 5870 at 975Mhz.  This is true for both kernels.  changing WORKSIZE and AGRESSION has no effect.

GPU usage is reported at roughly 60% according to GPU-Z.

standard poclbm gives me ~405 Mhash/s...

Am I doing something wrong?

I'm running SDK 2.4 on Windows 7 32bit.