But you're running it all in DirectX 9 verses 7 right?

Which track and which mod T? I could compare for you m8?

Btw DX9 is a huge jump compare to 8.

Have you tried with dx8 now?

I think x1900 supports that right?

I will have a look about and see what I can find out about it.

I usually leave DX set to auto in the rFactor 3D config, I seem to have less issues that way as I think some tracks were written for specific DX settings? or I heard that along the way somewhere

you have the latest driver I presume?

If an earlier driver may help, let me know T I have all versions going back to 7 on my PC, I can get them to you some how m8... I don't have the mod you were running but I will go see what 25 Indy or Champcars are like there and let you know

EDIT - tested the track with Indy Cars...

I was getting close to 80 Frames a second there with the following in game settings:
Circuit Detail: Full
Player Detail: Full
Opponent Detail: Full
Texture Filter: X16 Anisotropic
Special Effects: Full
Shadows: Low
Shadow Blur: Off

I turned Shadows to Full and turned on Blur to find my card wouldn't go above 60 FPS. Again I have DX set to auto so I am not positive which shader level was being used.

Try setting you DX to auto for rFactor and tune your shadows to low and turn blur off, see what shakes? if there is no change, I suspect there could possibly be a issue with the card.

I run a 1950 Pro which is one step up from the 1900 and should be a good comparison