I have installed the game on the following on separate Windows XP SP3 computers:
Pentium D 3.4GHz 800FSB, 4 GB DDR2 800MHz mem, SATAII HD, 1 GB 9400 vid, Gateway MB no over-clocking, BTX style
Core 2 Duo 6400 (2.1GHz slightly overclocked to 2.3), 1066FSB, 2 GB DDR2 Corsair mem (4-4-4-12), SATAII (SSD), 256meg 7600 vid, BIOSTAR MB G41-M7
Clearly the SSD drive computer loads much faster. Neither system is running System Guard and have the same AntiVirus, etc. As an example, Big$Baddest loads in about 4 minutes.
I may swap the Pentium D into SSD computer since I suspect faster CPU combined with SSD may be even better. I use the SSD as the swap file in Windows also. The operating system is on a Barracuda 250 GB drive in the 'SSD' system and I put software and games onto the SSD.
I would like to build a Dual Core 8500 system and use a 775 cpu board with DDR3 memory since its cheap. But I wonder what effect large amounts of memory helps the game?
The game runs fine on both systems though there is an occasional crash that is getting rarer.
Sounds like pretty fair specs. I've been looking at those SSDS, they sound like they really speed up the disk access. To get an idea of memory uses in the game, you can load one of the larger scenarios and press F1. this should display information on both memory usage and video usage.