For anyone considering dual core cpu upgrade, I strongly recommend it.
My system is based on this:
MSI Nforce3 socket 939 mobo with AGP slot
nvidia 6800GT mildly overclocked
2 gig PC3200 memory
Soundblaster audigy2
I had an A64 3700 San Diego, 2.2ghz with 1 meg cpu cache.
New cpu is A64 X2 4400, 2.2ghz, 2x 1 meg cpu cache.
Because of my RL flying, Andy Hollis' old saying "framerate is god" is a true statement for me. Stuttering totally ruins the gameplay experience for me. I run a 60hz refresh rate LCD monitor, and any framerate below about 40 fps is noticeable and unacceptable to me. Primarily, the problem I have is that objects and the horizon seem to stutter when rolling whenever the framerate gets below about 40.
My old settings - 512 textures, 1280x1024, sliders around midpoint, 2x or 2XQ FSAA. This would get me maxed 60 fps most of the time, with drops to around 40 in furballs or near burning fields. Tower FPS between 35 and 45.
After dual core cpu upgrade, I run 1024 textures, same 1280x1024 resolution, I've upped the sliders another 1/4 of the way towards max, and even better I now can run 4X FSAA. I wish I had a 7xxx vid card so I could run transparency FSAA and get rid of even more shimmering in AH trees, antennas, etc, but I don't have one.
Keeping in mind that the new X2 cpu has the exact same clock speed as the old cpu, this is a HUGE increase in performance playing AH. I simply never expected this to be the result and didn't buy the upgrade to help out AH, but the results were amazingly good in AH for some reason.
The only downside to the upgrade was that my old USB webcam seems to crash my computer now, so I need a new webcam. Everything else seems work better/faster. Given the very very low cost of AMD socket 939 X2 cpus now, I STRONGLY recommend this upgrade for anyone looking for a little more oomph out of their A64 system. Make sure you apply the patches, use a recent bios, and don't expect a miracle with single threaded apps unless you also increase the clock speed, but for me it was a great upgrade.