Run and download the final Doom 3 patch. The beta has been floating around for awhile, but this version is the one to get. Its long list of changes can be found at this link as well. Among the things that stand out, are the tweaks to damage in multiplayer, and some stability fixes. I've seen one of the listed crashes, so I'm downloading the thing right now. One note of caution is that the patch will reset you to the beginning of the map you're currently playing. So don't intstall it until you've progressed to the beginning of the next level.
