I'm running FSX with Acceleration and averaging excellent FPS. I followed Nicks tuning guide at the following site
http://www.simforums.com/Forums/topic29041_page1.html
I'm averaging in cities such as KLAX 30+FPS with sliders set as per Nicks guide. Away from large cities or over ocean the FPS can go over 100 FPS. This motherboard and processor is amazing. The motherboard was selected as best buy on Toms Hardware site. Purchased mine as a DIY from Newegg for a total of $816.00 out the door. Not going to need to upgrade for quite some time. If your interested in a new processor for FSX/Gaming stick with the i5 vs i7. The price vs performance is far better with the i5 2500K than the i7. The only extra with the i7 is the addition of Hyperthreading (useless in gaming).
My hardware is as follows:
Windows 7 Ultimate 64bit SP1 (Fully updated)
Rosewill Challenger Mid tower (Black)
Core i5 2500K (non clocked)
Gigabyte GA-Z68XP-UD3 motherboard (BIOS F8)
8GB G-Skills Ripjaws DDR3
XFX HD Radeon 6870 1GB GDDR5 256bit PCI-e (CCC-11.9)
Sound Blaster X-fi Xtreme Gamer
Seagate SATA-3 1TB 7200RPM (OS Drive)
Hitachi SATA-2 1TB 7200RPM (Game drive)
LG Blue Ray Writer
Antec 650 watt PSU