Having not been able to distinguish MSAA 4x and MSAA 8x I was beginning to wonder if my driver was faulty.
However having experimented a bit more – I can distinguish between 4x SSAA and 8x SSAA
So the AA pixel samples is set in fsx.cfg and I have set SSAA in the driver
Dx10 SSAA 4x
Dx10 SSAA 8x
Look on the door of the car.
Also zooming in on the car roof at 800%
You can I hope (even allowing for compression on the web page see that the gradation at 8x is more subtle.
So that con firms to me that the fsx.cfg MultiSamplesPerPixel setting does work for 8x for DX10.