I have built over 6 completely new systems during the past years using the IL2 1.0 through current 1946, patched 4.09
No stutters
Think about it. If you have built and used several systems and all of them have done the same or similar things. Take a hard look at your hardware, and peripherals. Especially any hardware item/s that you have used on all those systems.
Soundcards and acceleration were a big bugaboo for a long time. I haven't used a standalone sound card in the past three systems I've built.
I use the mobo onboard sound, and haven't had problems.
We have all had some types of issues with each system upgrade, and often IL2 addons and patches. We work through the issues and move on.
I've had powersupply issues as well. I moved up to 750Watt last system upgrade, 7 onboard fans, 3 additional fans on the mobo, 1 fan on the Videocard 8800 GTX OC
What I'm saying.. you may think you've done everything, but you'd be surprised sometimes just how far you have to go with hardware upgrades. Changing one thing can bum the works.
You can still get good tech help on Ubiforums Community help
http://forums.ubi.com/eve/forums/a/frm/f/49310655
good luck