Radeon 7000, an old ATI card for less than $30 nowadays, comes with DirectX 9. I know because I had one. It's a decent card for running simple games on or for those with almost no budget. I have Radeon 9600 XT myself of which is probably 18 months old or so (given the driver's date of July 2004 (the ones on the CD anyway)). Radeon 7000 is probably 3 or 4 years old. I'm unfamiliar with Nvidia's timeline so I don't know older Nvidia cards and what they have. When I had Radeon 7000, it ran A6 just fine (6.22 anyway, the last A6 version of running on the Radeon 7000. I might upgrade again, but this PCI-express thing is a limiting factor....

Look at the minimum system requirements on Conitec's main website. Even my 5-year-old computer could run it, but barely (except the video card). If all else, just run the engine with -w3d to minimize incompatibilities with old systems.