Recently we posted some Speculative DOOM III System Requirements that where then confirmed by id Software's John Carmack and now we have found an article posted over at Gamezoom.net, that put's the Doom III system requirements on test. Here's a quick translation as the site's in German.
DOOM III alpha is being run on 7 PC's with different configurations. This should give you a good preliminary comparison with the final version of Doom III as this will be optimised for most hardware.
Doom III System Requirements On Test
Doom III System Requirements On Test