Im no expert, but I had the same problem, and Nick helped me fix it. If you want, read the thread in which he did it:

http://www.simviation.com/cgi-bin/yabb2/YaBB.pl?num=1223553815/0

hardware is somewhat diff, but it should still work i think.

First, I would get rid of SLI, no good for FSX. Also try using the beta driver Nick recommended to me in the thread, that also helped.

Also, I noticed you have XP SP2, i would get SP3.

Are you sure you defraged and followed the optimization thread to the word?

If so, did you do the defrag AFTER you installed FSX and Acceleration?

And lastly, I would leave FSX tweaks stock, and then use the general recommended settings, like leaving global on high, stuff like that, you can find it all over the place, including my thread, and play with AUTOGEN, AI, VEHICLES, one a time to try and isolate the problem if still there.

Another thing that has worked for me is to run FSX in a clean re-start. Make sure you have 30 or less processes. Also, sometimes I run FSX, close it, then run it again, and it seems like everything gets a little better.

Other then that, you're probably gonna have to wait till someone that knows what theyre talkin about comes through and works with you on your prob.

I followed Nicks list  and did it all after I had installed fsx and acceleration.
I am thinking about doing it all over again..As far as getting rid of sli, I also play other games which benefit from sli. I tried disabling sli, but the stutter was still there. Maybe Nick could help me out? Oh, thanks for the link Flavio, I am going to go read up.

I tried disabling sli and the stutter was still there. I am sure it's probably something with my system, just not sure what.

What is running at Windows boot?

What AV is installed and is there any other secutiry software running on this machine?

What addons are installed.. ie UTX, GEX, etc

Post the settings you are using for each tab

Use the software CPUz to check the memory speed and timing in Windows... google CPUz


and I dont care what anyone says.. SLi is as worthless as boobs on a bull to FSX unless you are running above 2000x resolution and 16-32AA

NickN wrote on Nov 21^st, 2008 at 12:48pm:
My reply was to say that SLI was not interfering with FSX, i never said it made the graphics better.

I need to know what may be running in the background on this system before I can go any further

its possible you are clean and that is not an issue but before I go spinning wheels I want to be sure

Click START - RUN

type: MSCONFIG

Click the STARTUP tab and post the list

Download and install Spybot Search and Destroy

When you install it, elect to UPDATE during the install, UNCHECK TEA TIMER, do not use that. but do allow the IE protection

Once installed the first start wizard will appear.. do not backup the registry but DO download ALL available updates.. then IMMUNIZE the system.

Once that’s all complete, click the MODE menu, select ADVANCED

New options will appear at the bottom.. click TOOLS - SYSTEM STARTUP and post a screenshot of that list


Reboot

CTRL - ALT - DEL  when task manager appears click the PROCESSES tab and post a screenshot of that list


Open Spybot and verify there are no more updates... run the update and if there are, download them and then immunize again... after, click Search and Destroy, run the scan

grab a screenshot of what it finds and post it

Have it repair everything it finds and follow the directions if there are any

After all the background checks are done, click here and set up FSX exactly as I posted in this list:

http://www.simforums.com/forums/forum_posts.asp?TID=26410&PID=149607#149607

EXCEPT

Set AL and GA traffic to 30, airport vehicles to LOW, Cars to 8, ships and boats to 20 and autogen slider to 3/4..  make sure you look at every setting in the images and match it

Keep your monitor resolution but set frame lock to 30


experiment with 30 and unlimited... try both becasue with FSX Unlimited will run smoother in some scenes and locked 30 will run better in others

While you are testing, drop autogen to 1/2 but do not lower it anymore... and, you can try droping Scenery Complexity one notch, but no lower

Use KSEA Seattle area for test and setting up... fly strait out RW 34, past the city, past the lake and all the way out to the next airport and then turn around and come back, land on RW16

I will tell you right now that FSX sutogen is rediculous .. its overload for most systems so if you get GEX it will help because it will remove the AG load and upgrade the visuals at the same time

That is one addon if you fly in the US, Canada or Alaska that will help performance


Disable SLI when running FSX and make sure the settings I posted are what you are running in Nhancer. Instead of 8xS AA, try Multisample 4x

http://www.simforums.com/forums/forum_posts.asp?TID=27540&PID=156769#156769

See if it runs any smoother