Re: GeForce FX 5950 and Source DX 9 performance...
I've never really had a play with the late models of the FX series, but as I say, if simple FX DX 9.0 performance can't explain this problem, it really could be that it's trying to emulate some SM 2.0b functions. Once again, I stress that I don't know how well an FX5950 should perform when doing full precision shader calculations under the SM 2.0 spec, but if it really should be that much better than the 9600 under such conditions, then something like that could EASILY explain it. Any of you remember running NV30 emulate back in the day? Well it'd be like that, only possible somewhat faster as nowhere near as much would be emulated.
Dr Possible: Core 2 Duo E6400 on Gigabyte GA-965P-DS4. Galaxy GeForce 7600GT. 2GB Corsair XMS 2 DDR2-6400 RAM (CL5). ATi Theatre 550 Pro. Windows XP MCE. All stored in Piano black Antec Sonata II, with a broken door.
Mobile: ASUS M2400N, Pentium M 1.5 GHz. 512 MB DDR RAM. Intel EXTREME graphics. Windows XP SP 2 / Ubuntu 5.10.
Ridiculous DOES not have an 'e' in it. It comes from "ridicule" and has less than nothing to do with the colour red.