I've found some more info on the Geforce FX 5200 series and it seems the card can't do ps/vs 2.0 using DirectX 8.0, however it can use ps/vs 2.0 in DirectX 9.0. I think in this case the A6 engine simply displayed the max for DirectX 8.0 indeed. This might explain why it didn't run any ps/vs 2.0 applications back when I tried, perhaps they were all DirectX 8.0.
http://www.guru3d.com/article/content/59/2/