questions answered by robert duffy, lead programmer, id software

Q: share your thoughts on the latest gneration of graphics technology as it relates to doom3, is one better than the other?
A: both cards to an excellent job running doom3. right now, the nv40 edges out the r420 in overall speed, but they are both quite capable of running doom 3 in high quality with very good frame rates, although there is a higher quality setting called ultra.

Q: how many unique render paths does doom3 have?
A: four rendering paths are supported: nv10,nv20,r200 and arb2
the arb2 path does support fragment programs,which we use for a very cool heat shimmer effect and some other effects, although these effects passes are not critical to the overall look of the game.

Q: does doom 3 run better on video cards with 256mb of video memory rather than 128mb?
A: 64mb has downsized certain classes of textures to get them to fit. On 128mb cards, we run everything at full resolution but use compressed textures. On 256mb cards, we run with compressed diffuse and specular textures and uncompressed normal maps. In ultra quality mode, everything is uncompressed but most levels require about 500mb of texture memory, so we dont enable this setup by default on any currently shipping video card.
Doom3 automatically chooses the best options to use and run well, and someone with a 128mb card will get great visuals and good performance right out of the box.

Q: assuming that the only difference between the two systems is their graphics interfaces, will a pci express based pc run doom3 faster than an agp system?
A: pci express should make no noticable difference.

Q: Given a 32-bit windows environment, how much ram should a gamer have on his pc if he wants to see doom 3 running at its best? What about 64-bit windows?
A: 512mb is ideal, and if your trying to run the game in ultra quality, youll want 1gb ram or more. We dont do anything specifically for a 64-bit OS

Q: Whats the least amount of ram a fella should have if he wants to have a good doom 3 experience?
A: 384mb ram, although 512 is highly recommended.

Q: Same question, but regarding one's cpu: whats the least amount?
A: a 1.5ghz p4 or the amd equivalent.

Q: tying it all together, if you were to build three doom3-lovin pc's,which components would you want to see in a:
low end system:
cpu: 1.5ghz p4 or equivalent
ram: 512mb
video card: nvidia geforce ti 4800 or ati radeon 9500

mid-range system
cpu: 2.4ghz p4 or equivalent
ram: 1gb
video card: geforce 5950 or ati radeon 9800 pro/xt

"robert didn't offer any current generation high end suggestions. instead, he told us, "doom3 has settings that will make the game look even better on hardware that doesnt exist yet beyond just upping the resolution like in most games", but for high settings we recommend:
cpu 3.4ghz p4 or amd equivalent
ram: 2gb
video card: geforce 6800 ultra or ati radeon x800 xt