August 13th, 2014, 08:47
You should always build your own. It's fun, the cost can be much reduced over a boxed PC, and you have control over all parts. Plus everything only fits one way and there are tons of videos on youtube showing you how if you've never done it before. I do this every few years since my first one back in 1988.
The specs on papab's system above look good but I would get one more Gig memory on the video card and for FSX you won't use more than 4Gig RAM. So go with 8 rather than 16 and apply that money towards the video card upgrade. Just my opinion.