Doom 3, please help

I have just bought Doom 3 (Green Pepper "nice price" edition) and it does not run as it should.
As the game is some years old it should perfectly run on current computers, shouldn't it?

My system:
Intel Core 2 Quad, 2.44ghz, Q6600, 3 GB ram, Geforce 9500 GS 512 MB, Vista 32 bit SP1.

I tried to run the game with high settings, 1024x768, antialiasing x8 and everything on.
Doom was published in 2004 so there should not be a problem with current computers.
What could be the problem?

I don't think it works on Vista?

It does...there is a patch. I had to deactivate AA. Now it works.