The Dead Space Society

First, here is a link to the Hard|OCP Doom3 hardware guide. This will give you a good idea what you system could be capable of in reference to similar systems.

Hard|OCP Official Doom 3 Hardware Guide

Also, I would not get too excited about PCI-X right now. Benchmarks suggest very little performance increase over 8xAGP currently. PCI-X cards are still in the begining phase of the technology, I would wait until the next product cycle roll out for video cars, or at least until PCI-X is available for AMD motherboards so you have more of a choice and more competition to deliver performance.

I bought a new 9800 Pro for playing DOOM 3, and also a P4 2.8 to replace my Celeron 1.6. I was quite disappointed that I could not run the game at 1024x768. That is until I followed the advice given at this site:

Optimize XP for gaming

By setting up a new hardware profile and disabling some services for that profile, I was able to get Doom 3 to run at 1024x768 at medium detail settings with only an occasional studder. I highly suggest doing this for gaming if you are having a hard time getting it to run. While stopping services may seem like a waste of time, Doom 3 will use every extra bit or processing power and memory the system has, both in the vid card and the CPU/motherboard - so give it all you can.
You may also want to look at overclocking your CPU, memory, and video card. I have all of these things OC'd on my system, which can make quite a difference.

One other thing you may want to consider is the affect of sound on your games. If you are using on-board audio, it will drastically affect your game play. Tom's Hardware did an article on this a while back that showed a 10 to 15% performance loss with on-board audio. Below is a link to the conclusion page.

Tom's Hardware Audio and Games (conclusion)

You can find 5.1 surround sound cards as low as $13 at NewEgg.com. Though I don't know how well those would be supported. Creative has it's Sound Blaster Live! 5.1 at NewEgg.com for $29. Either of these would take some or all of the sound processing overhead away from your CPU, and you can always transfer the card to your new computer. I suggest 5.1 surround becuase Doom 3 supports it, and running it in 5.1 mode really adds to the game. (I am using the Kinyo surround sound headphones, which I will review when I am done playing through the game.)

Hey Crow, if you manage to get it to work on your system, check this review out for headphones...

Kinyo 5.1 Headphones

I bought these (actually they were a gift from my wife that I picked up to saver her the time) specifically to play Doom3. Man! These really get you in the game. If you already have a 5.1 speaker setup and don't have to worry about wife and kids, then you don't really need them. However, for those folks who want to really get into Doom3, but don't want to wake the rest of the family, get a pair of these - then play at night with the lights off and the headphones up. WOW! 5.1 really does make a difference.

Huh?

Well, Doom3 is running pretty nicely now. 1024X768, med., nice and smooth. I had a spare HD laying around, so I threw that in as a dual boot with a fresh XP install. Updated to SP2, installed newest Catalyst, whacked some processes, and bumped My refresh rate from 85 to 75. Not sure what did it, but I am VERY happy with this card now.

Oh, and Roach, those phones look like a good deal. Unfortunately, I got all psyched to pick a pair up on My way to work this evening, not realising that Bestest Buys/Circuit shitty wouldn't have them. Well, I wasa gonna pick up some tunes from Amazon anyway.