Well, I always move around the 150 EUR range, where you can find a lot of good cards. I think that is the minimum price for a gfx-killer game, like FS

It is always a good question, if you want to meet the 2 fanclubs, to disagree about the 2 brands

but I think for gaming, there is not a big difference between NVidia and ATI chips. If the card had 128 MB RAM, then simply select the most expensive one from the list, until the price you are able to pay...then you surely have a very good card, and more freetime to think of more important things about the life
