Got FSX thinking I wouldnt have any problems considering what I have... I was wrong. I noticed that people were saying there FPS sucked! I am also having that problem

I just got done building a new PC as an early X-mas present and it cant even handle FSX!!! Here are my specs and tell me what you think?
CPU: AMD 62 X2 4200
MB: A8n32 SLI Deluxe
RAM: 2gig
GPU: I am running 2 in sli GeForce 7900 GT KO 256mb
That setup right there you would think would have a problem... Even when I turn things down the best I will see is around 10fps to 5fps
WHAT IS THE DEAL!!!