I have a $750 budget for a gaming PC but am willing to raise the price a couple hundred dollars if it means I can play what I want to play. I would like to play game like Fallout and Skyrim on ultra settings. Minecraft with Sonic Ethers Unbelivable shaders mod on ultra. And Arma III on high to ultra. I will be playing on a 1080p monitor. Thank you! Not including a operating system but on that note, windows 7 ultimate or windows 8.1 pro for gaming?