Hi, guys, I've been browsing these forums for a solution to my problem for about two months and something. On to my problem: my FSX works ok without the SP1 or Acceleration Pack. Not great since it struggles to get around 25 fps. After installing SP1, I got a nice improvement, framerate goes easily around 50-60 fps in not so detailed cities (S

Are you using:[bUFFERPOOLS]Poolsize=5000000With your cards mem you could go 6 to 8 million.Anti virus turned off?Have you tried deleting FSX.CFG and letting it rebuild?What happens if you lock your FPS at 20?When the FPS drops to 5, does it stay there or instantly jump back up?Have you tried "Driver Cleaner PE" to completely remove video driversbetween driver installs?Server 2003? Set to optimize system processes or applications?What does task manager show? Are both cores being used?Can you turn off uneeded services? Everything look good in device manager, no red X's or !'s?Are you running the latest DirectX version?

Yes for all your questions. Like I said, I've runned out of ideas. Nothing seems to help. It's crazy. The Bufferpools flag helps a bit if I set to original value pre-SP1 (1 million). But it does not help much. About FPS lock, it stutter the same with no regard where I lock it. And when the FPS drops to almost halt, it stays there for a second or so and then goes back to 20 or 40 or something like that before stuttering even harder again. I've tried to change the render ahead settings of my card, with no success either. One funny thing I didn't mention, when it start this stuttering mess, if I pause for a bit, the framerate normalize for a few moments. Then starts the crazyness again. I don't know who I should blame, either ATI for their lame drivers or Microsoft for the lack of support with these crazy stutters. I love FSX, but would love even more if I could use it.Thanks for trying, fellow. Still waiting for that magic trick to make this thing work like it should. ;)