How full are your harddrives, and have you done any tests to see how your hard drives perform? After 80% capacity for a hard drive, performance dips for a lot of hard drives.
Regardless, let's use the process of elimination.
1) It is very, very unlikely that a new processor like this would have any effect on the load times of a game, especially a bad one. If you look at your cpu usage while in task manage during the time the game is loading, your processor has a very, very small chance of staying about 50% for very long. Also, it's not a dual core issue. Even those games weren't written for dual cores, this means that they were not optimized for it, windows should still handle distributing among both cores what would have previously been made for one. This will not affect load times.
2) You have 2 gigs of memory, and the most memory intensive games I've seen take about at most 1 gig, so you should have no problem loading the models into memory and what not. Really, you shouldn't.
Did you turn up the graphics a lot since last time you played? What exactly has changed? I'm not an expert game designer, but if you change the texture quality, I'm pretty sure that requires more and larger files to be loaded from the hard drive.
3) I can't imagine the video card slowing down your loading times.
What else does that leave?
and "ASUS K8N-E Deluxe nForce 3 250GB".
250 GB? What do you mean?
Perhaps you should try benchmarking the hard drives. Also, how much faster did your old system load this game? In under 2 minutes? in under 1 minute?