FAQ How to configure FSX
Defragment your harddrive after installing FSX or huge add-ons like sceneries, complex aircraft, AI etc. Install the FSX Service Pack 1 (minimum) or better Servicepack 2 or Acceleration-Pack (recommendet). Read also the thread "How can I configure FSX" below. Download the FSX Service Packs at fsinsider.com [continue]
Use the Tool "Flusi-Fix" by Wolfgang Picheta and read and follow the tipps on his site [continue]
No, if you have an actual PC with a good CPU-speed and you have allready installed the SP1 and SP2 for FSX, and you follow the tipps above, it will work pretty fine. Take a look to the System requirements [continue]