Your in the wrong forum for FSX. This forum is for X-Plane only.
As FSX is now dead the change to X-Plane will make a difference to your flight simulation. X-Plane operates as 64 bit allowing up to 64 Gb of working memory whereas FSX is old 32 bit which limits you to 4gb of memory irrespective how much memory your computer has.
Try the demo version which can be downloaded at http://www.x-plane.com/desktop/try-it/ From the demo version all you have to do is pay for the already downloaded software and you will receive a product key to run the system.
Also have a look at the minimum and recommended specifications to run X-Plane 11 which can be found at http://www.x-plane.com/2016/11/x-plane-11-system-requirements-announced/
Hope this helps and hope to hear that you make the change.