Some of your specs above, I'm not that familiar with, but it sounds like you have enough to run the game pretty well. I
can tell you "Gameshadow" is not the problem. This is a program that reads what games you have installed and informs you of what updates or patches are available for your installations. Also, I have heard of issues with SLI configurations. You may want to search the threads for this (SLI) kind of info. Wish I could be more helpfull. Hang in there, the game is well worth it. I'm sure someone more familiar with your setup will pipe in here with some better advice. DON'T GIVE UP! You'll be glad you didn't and there are many people here that are more than willing to help you. Just be a little patient
. AND....BTW Welcome to Subsim!