hello,I've returned to FSX after a little break, and restarted installing Acceleration pack on top of previous FSX installis it my impression only that Acceleration has slowed down game performances?:-hmmm

Installing Acceleration installs SP2 and is suppose to install SP1 if it's not already installed. For some reason that didn't occur when I reinstalled FSX so I installed SP1 then SP2 located inside of the Acceleration package. If you have the Deluxe version of FSX, you should also install the SDK updates too. SP1 provides most of the tweaks and fixes for FSX. It's pretty much a mandatory requirement to install if you want the full benefits of FSX. SP2 provides support for DX10 and is NOT required if you do not meet system requirements for DX10. However, I believe SP2 changed FSX.exe to tell your system it uses more than 2GB of memory which helps eliminate out of memory errors. You can do that manually though and there are posts on AVSIM that tell you how to do it (search for OOM or out of memory in the FSX Forum). Acceleration is an addon that includes more aircraft and missions. That's it! You can uninstall Acceleration if it's causing you performance issues and simply download and install SP2 alone (free) from the FSInsiders website. SP2 provides better performance (FPS) if DX10 Preview is checked in the FSX settings; however, you must have Vista installed AND DX10 capable video card(s) for DX10 Preview to work. You can also gain better performance by lowering the scenery sliders within the FSX settings, lowering the amount of autogen and lowering the percentage of AI. There are a lot of suggestions on how to do that within this forum and you will have to do some research on your own to find the "tweaks" that fit YOUR system. Hope this helps.Best regards,Jim

thanks Jim,sadly I had installed SP1, I don't have Vista, I have 3Gbs, so it looks like there's no choice other than lowering graphic settings:-hang :)