I was talking to Train_Whiz but if you are having problems with long loading times (and how long is too long??) then you may also have configuration problems.
Just because you have a system that is "more powerful" with a lot of Video RAM (and I don't know where the GForce XG 440 fits in the hierarchy of video cards) does not mean that you have the system configured correctly. Do you have the latest drivers for all the built-in hardware, not just the video card?
Too many threads in these forums start out with the original poster claiming that TS12 is a dud and end up, after some discussion, with that same poster discovering that his specs were not really up to scratch or he had driver issues, or a host of other software and/or configuration problems that were the cause of his problems.
I bought TS12 expecting some thing good, for multi players it probably is, but for people like me who like to build our own tracks and just play trains, I wasn't impressed. I created a small amount of track and had my 60 trains in the yards I create, 1 loco a train 10 trucks, I usually run the trains every so often when I have built some track, I pressed drive now and it wouldn't load, I tried it several times after I put down for train drivers. Never loaded once, I have now gone back to TS2009 which I know will load with 60 trains and with longer trains.