I use windows 8.1 for FSX and I simply cannot use free flight without DirectX10 on as it won't even let me use free flight mode. I was wondering if the PMDG aircrafts are compatible for Directx10 as most add on air crafts are not built for DirectX10 as they appear all white inside and out white.

As far as I recall the official answer is that the aircraft are not "DX10 Supported", however people have used them successfully.  I can't locate the exact verbiage right now though, so my apologies if this is not correct.

I have been on dx 10 for months now and haven't seen a problem yet.

 

I have the ngx, 777, md11 and 747

As far as I recall the official answer is that the aircraft are not "DX10 Supported", however people have used them successfully.  I can't locate the exact verbiage right now though, so my apologies if this is not correct.

http://forum.avsim.net/forum/644-the-official-dx10-scenery-fixer-support-forum/

I have been on dx 10 for months now and haven't seen a problem yet.

 

I have the ngx, 777, md11 and 747

So the planes don't appear to have white textures or anything?

I use the DX10 Preview too w/ no issues a, I actually started using it to cure my kind of OOM w

Error and it did.

 

Richard Bansa

So the planes don't appear to have white textures or anything?

 

Sometimes there is a longer texture load delay when switching to the VC but its negligible. Other than that I have only seen positive results. I get way less OOM's. I have only had one or two since switching. I used to get them all the time. 

All PMDG aircraft from the NGX work for me, I have noticed much better quality and performance too. Had no issues what so ever apart from the arm rest texture looking grey and night.

I have recently switched to DX10 too, mainly to try it out.

Take note, nVidia inspector doesn't work in the same fashion with directX10. Also, some higher Anti aliasing settings are, perhaps for the moment, unattainable as far as I can see. In SteveFX's fixed I can achieve 16x as a maximum, thanks to two powerful GFX cards, I was used to 64x on DX9.

In any case, the extra smoothness does seem very noticeable.

I have recently switched to DX10 too, mainly to try it out.

Take note, nVidia inspector doesn't work in the same fashion with directX10. Also, some higher Anti aliasing settings are, perhaps for the moment, unattainable as far as I can see. In SteveFX's fixed I can achieve 16x as a maximum, thanks to two powerful GFX cards, I was used to 64x on DX9.

In any case, the extra smoothness does seem very noticeable.

 

Thomas has some very good points. You will probably need to educate yourself about how to set up the software as well as nvidia inspector. The best resources are the authors website as well as the DX10 forum here on Avsim. Just keep working on it and it will be worth the effort. 

I've used the NGX with DX10 and it works fine. Only a tiny bit of improvement for me though, but I had some crashes that I didn't figure out the cause to, but was related to using DX10, so I'm back to DX9.