i agree, reinstalling DirectX and installing the newest nVIDIA drivers.

Also, HL2 aswell as many other games on the source engine and/or the Unreal engine are developed to run on as much confiurations as possible and (as phemox mentioned) have countless fallbacks. Only because they RUN, doesnt mean that they run PROPERLY.

Acknex doesn't have any of those fallbacks that I would know of.

Besides, I already said that the A6.60 engine works just fine for me ( I also have the commercial edition) and I have the exact same graphics card.