I never have FSX:SE running when I'm configuring PF3. I bring up FSX:SE after PF3 is ready to go. Am flying the PMDG 777 for the time being. Will add other aircraft after I've decided what to do with FSX:SE, such as dump it for P3D. As the Beatles said, "All it takes is cash". Or love, or something... I do have a ton of other addons, i.e. scenery, airports, GSX, UTX, GEX, FSGenesis Mesh, Ultimate Traffic II running alongside/inside FSX. I pipe in ActiveSky2016 from a second computer via SimConnect. Plus running Saitek Yoke, Throttle Quadrant, rudder pedals and the VRInsight MCP Combo II for Boeing. Lots of stuff, but it is a i7-6700K oc'd. One thing that made a difference was turning off hyper-threading. FSX just wasn't designed for it. Multiple cores, kinda, but multiple threads sharing a core, no. Would be better to have 6 cores but again $$$.
Do have a question. Does PF3, when running along side FSX:SE use any of the sim's address space? My sense is that it doesn't but reads contents of addresses/control blocks to exchange information with the sim. Today was the first time I ran out of memory in quite awhile. There is only so much you can do in a 32-bit address space. For the record I have 16GB in the PC.
Thanks for your efforts,
George
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Capt George - @7x7VirtualPilot