There are some good pci cards that have 256mb onboard. Pci is still limited over agp by the
long shot there. An equal match of installed memory generally runs smoother provided the
dimms are the exact same type and usuallt the same brand from the same production time.
Matched pairs of dimms are those that are pretested to work together on one board. Those
newer games always seem to run better with more available ram as well as having a good
VPU(video processing unit) on the video card itself which takes the load off of the installed
main cpu freeing processor time.
Some of the newer model pci type cards have dual vpus on them. Most of those are above
the basic pci type you are using however. There are a few things that can help with having
a more resource demanding game run better however. Using the msconfig utility a number
of non essential startups can be reduced to free up system resources. If you are running a
pci slot video capture device to later edit video or even a usb capture device you would then
uncheck the listings in the msconfig to manually start them when used.
If you are unfamiliat with the msconfig utilty the process is basic. You first go to Start menu
and drop down to the "Run" prompt there. Type in msconfig and press the enter key to see
a new display come up on the screen with several tabs. The last on the right is the startup
listings for installed softwares which also include the video and sound. Those you would be
keepoing checked unless an extra caused issues with Doom 3. Once you uncheck all of the
non essential items listed you then exit and restart the system with more free resources as
well as available memory. With XP the next tab is where to check the "hide all ms services"
to avoid disabling needed background items that are necessary. Video and sound there too.