Hi your machine will be more than fast enough for anything right now, bear in mind Doom3 runs in opengl which isnt ATIs strong point, nonetheless the game is hardly worth much effort as its really quite overrated and insanely boring. Im sure new games will come out shortly with the engine, which might actually have some playability. My advice to you is turn off AA and AF and get acceptable frame rates at as high a resolution as you can run via your monitor as you wont notice jaggies quite so bad at 1280x1024 or 1600x1200.
The point logla made is semi correct but ASUS have a newish motherboard out which you may want to look into at a future date - the
Asus P5AD2 Premium 925X. http://www.overclockers.co.uk/acatal...herboards.html
This motherboard overclocks extremely well and there are many reviews of it already such as the links below. I overclocked my engineering sample 3.4 775 EE to 4gigahertz with this board on air, but the unfortunate situation is there arent any great coolers out yet but im sure thermalright will bring out one of their acclaimed SLK sinks for this slot solution soon.
http://www.pcper.com/article.php?aid=59&type=expert
http://www.digital-daily.com/motherb...p5ad2-premium/
http://www.hardocp.com/article.html?art=NjM4
This motherboard does cost a small fortune mind you so you might be best waiting a while as your system should be capable of handling anything right now, the extreme editions are amazingly powerful CPUs especially with rendering, en/decoding and any form of intensive memory operations.
I am almost certain DELL use reference intel boards so you can use a tool which INTEL developed to safely overclock their own boards. its called INTEL CONTROL CENTER and if you go into the TUNE option then BURNIN you can raise the FSB by 4%, which I know isnt a lot but you will be running your CPU at 3580mhz from 3400mhz without any work whatsoever, the machine will reboot, play a little tune and alter the bios. At the time of posting it appears INTEL site isnt working for me, but the tool is available from major geeks
http://www.majorgeeks.com/download4028.html
Good luck, just make sure you check your motherboard is a built by INTEL board first.
