I can honestly say that I didn't expected RTW to run on my PC:

Celeron 466
512Mb RAM
GeForce 4 MX 440 64Mb

The big problem with this system is the lack of CPU power to account for high geometry and many troops.

From the start, I used the minimum settings available in the graphics options menu, including the smallest unit size and 800x600 16bit. It ran at about 3-5fps average with sometimes a high point of 9fps. Not very playable. Then I got an interesting tip:

Inside the file descr_auto_optimise_options in the Data folder, you can change (in the first line - minimum settings) the unit_model_detail setting from low to super_low. This minimizes the geometry of the troops to a setting that is not used on the demo, but that the game contains. So, instead of lowest you get a super_ lowest.

Needless to say that it doesn't look pretty, but makes it far more playable in my system. I got 7-9fps with highs of 14fps (small unit size and 800x600 16bit).

With 1280x960 16bit and max settings in everything, except shadows and antialiasing, I get 2-3fps with a high of 6fps...