So more and more people are running DX10 lately and everybody is so excited about how it provides an advantages such as in performance over DX9.

But in my case, things seem to work out differently. I have installed the fix by Steve, and it works, no more flashing/flickering, everything is working fine. But in contradiction to what many people say, I am NOT seeing an performance increase. In fact, I am seeing a significant decrease in performance. Now, I have got to admit I am using tweaks in my fsx.CFG to optimize my performance for DX9. I am not running loads of tweaks, but two tweaks I never fly without are PoolSize=0 and HIGHMEMFIX=1. The first one increases my framerate by around 50% in DX9 mode and the second one improves stability a lot. 

But here is the problem, this PoolSize=0 tweak does not seem to take effect in DX10. Whether I enable or disable it in my fsx.CFG, framerate remains the same. Only if I start comparing DX9 with disabled bufferpools to DX10 with disabled bufferpools, I am getting better FPS in DX10. So maybe it's somehow related to that.

Also, anti-aliasing doesn't seem to be working. I have an NVIDIA Inspector profile for FSX running 8xS + 2xSGSS + VSync + 1/2 refresh rate, and so on, but these things don't seem to be working for me in DX10.

I suspect I have forgot about lots of other settings.

Could I please get some help here?

Bufferpools:

With DX10 some of the calculations done by CPU in DX9 are transferred to the GPU. With bufferpools=0 you might be stressing the GPU a little too much. Try the recommended settings in the How to. I have always used bp=0 too, but with the following settings I didn't notice any decrease in performance in DX10:

 

[bufferPools]
BufferPools=1
PoolSize=10485760  //8388608   // 20971520 20M //5242880 5M //10485760 10M
RejectThreshold=262144  //262144 // 786432  //1048576  //262144 //  131072

 

Anti-alias:

The best settings for me are 4 X MS and 4XSGSS. With all the settings with supersampling (like your 8XS which is 1X2 SS and 2MS) my performance isn't great either. I don't know what's causing that, but 4X Multisampling works perfectly here.

In fsx.cfg add these lines to the [Graphics] section:

MultiSamplesPerPixel=4
MultiSampleQuality=4 (you can up this one I believe)

 

I'm running an I5 2500K @ 4.6 GHz and a NVidia GTX670 OC edition, so very similar to your specs.