I found two potential problems for 3DNOW users out there. The first one is that if you installed the patch, you are still probably using your old config. This isn't an issue except that version 1.01 of Sin turned off the "vid_checkamd" variable because at the time the 3DNOW support was not done. This variable was then saved in your config.cfg so by updating to version 1.03, you still don't have 3DNOW support because vid_checkamd is set to zero not 1. To fix this either edit your config.cfg in base/players//config.cfg or create a new player config.

The other problem is that the latest changes to the renderer for the mission pack Wages of Sin have not been 3DNOW optimized and therefore do not show up. 2015 had added additional particle effects that are currently not supported in the 3DNOW enhanced, ref_gl_amd.dll. I am taking steps to make sure that these changes are integrated in the near future.

Thanks go to David W. Anderson for finding out the reason, he wasn't getting 3DNOW acceleration.