I'm running FSX Acceleration on Vista 64-bit with an nVidia 9800 GTX+ card. This means I'm DirectX 10 Preview mode compatible, and I've been enjoying it for many months on-and-off. However, the checkbox for DX10 Preview has suddenly disapeared:Does anyone know why is might have gone away? Its as if FSX no longer thinks I'm DX10 compatible.I haven't changed any hardware. I have installed one bit of software before I noticed the change, Just Flight's Traffic X (with SP1 update). I doubt this is the culprit though. The only other thing I remember doing was updating the DirectX 10 drivers by downloading the latest version dated March 23rd. Has anyone had any problems with this?Since then I wondered whether my nVidia drivers needed updating, which I've just done. These haven't brought the DX10 Preview checkbox back though!Does anyone have any ideas??

The only other thing I remember doing was updating the DirectX 10 drivers by downloading the latest version dated March 23rd. Has anyone had any problems with this?

I've never manually updated DX10 system files, as Windows Update takes care of all OS updates, DX10 included. You should use Windows Update to let Vista handle any update of DX10 system files. Could you provide an url to the download site for the DX10 drivers that you downloaded?Have you tried to revert to a previously saved restore point?

Very weird indeed!Have you tried creating a new FSX.cfg?

Your resolution is set at 16 bit. DX10 will not work at 16 bit resolution. Change your resolution to /32.Best regards,Jim

Your resolution is set at 16 bit. DX10 will not work at 16 bit resolution. Change your resolution to /32.

Good point Jim!However, I changed back to 32-bit and the DX10 checkbox hasn't reappeared, even after restart.The rebuilding of fsx.cfg sounds like it could be a winner, although I'm rather hesitant. I also looked for hits regarding Traffic X and fsx.cfg and came across this:http://www.justflight.com/faqs.asp?drdProd...ffic%20X#FAQ405This says that paths are added to fsx.cfg (although the date on the fsx.cfg doesn't tally with this). I can't imagine these would change anything to do with DX10, but then I guess its worth a shot.cheersAndy

Rebuilding your fsx.cfg file should be painless. All you need to do is get rid of it, and the next time you boot FSX, it makes a new one. Afterwards, you'll have to reset some of your settings, though.When I say "get rid of it", you can be adventurous and delete it, or you can be cautious and rename it and place it in a folder you can find later. That way if you wish to restore your old .cfg, just rename it back to fsx.cfg and put it back in its place.Jeff ShylukSenior Staff ReviewerAVSIM

OK, I deleted my fsx.cfg and then let FSX make a new one. However my DX10 Preview checkbox still hasn't returned! Help!

OK, I deleted my fsx.cfg and then let FSX make a new one. However my DX10 Preview checkbox still hasn't returned! Help!

Try reinstalling your Nvidia driver.Maybe something wrong with it

OK, I deleted my fsx.cfg and then let FSX make a new one. However my DX10 Preview checkbox still hasn't returned! Help!

DX10 Preview came out when FSX Acceleration (AKA SP2) was released. I would reinstall SP2 or Acceleration (whichever version you're using). It looks like it did not install properly.Jim

Hold your horses!Why not try to run DXDIAG and see what Vista has to say about it?Seems much easier than uninstalling and reinstalling FSX.

Many thanks for the Heads Up on DXDIAG. It tells me I have no problems, and that I'm running DX10.I've gotta say I'm not in a rush to reinstall Acceleration or FSX. DX10 has been working fine ever since I installed Acceleration on my DX10 compatible hardware (i.e. a new PC). Its only recently that it has "disapeared", so I suspect external influences, such as drivers or 3rd party addons.I reinstalled the nVidia driver (182.50_geforce_winvista_64bit_international_whql.exe)... but to no avail. There were no problems/warning/errors... but still no DX10 Preview checkbox either!

Just uninstalled Just Flight's Traffic X and restarted. That wasn't it either, still no DX10 checkbox. I now face the prospect of unistalling more things, or uninstalling Acceleration itself...

Just uninstalled Just Flight's Traffic X and restarted. That wasn't it either, still no DX10 checkbox. I now face the prospect of unistalling more things, or uninstalled Acceleration itself...

If it comes down to an reinstall, before you do that, try using the repair option. You may be missing a file that repair will fix the problem without having to do the uninstall. That should be your next to last resort, last being an FSX reinstall.

FOUND IT! :( I now know what the problem was. I decided to work backwards and uninstall every 3rd party addon or driver one-by-one, restarting and opening FSX Acceleration each time. I discovered the problem is a 3D driver I installed for ColorCode. This allows you to use brown/blue glasses to fly FSX in 3D. It is great stuff and I recommend it. I used their iZ3D version 1.10 Beta 3 driver from here:http://www.iz3d.com/t-dcdriver.aspxFor some reason (does anyone know?) this removed the DirectX 10 Preview check box in FSX Acceleration. When I removed the driver and restarted the check box was back again.Phew! At least now I know.I just have to make a choice between DX10 or 3D, until a suitable ColorCode driver comes along.

From what I recall, some (or all) current 3-D colour drivers can't use DX10 shaders, so you default back to DX9. When you use anaglyph colour (green/red for instance), your video card has to make two passes to make one image, doubling the time and resources needed to make one field of view. Any shader you add to that will also need at least two passes, one for red and one for green. The result is a slide-show, an overheating video card, or both. To speed up the frame rate, most anaglyph drivers brutally strip shaders and any other embellishments. Usually, stereo visual drivers are based on much older drivers than the current mono drivers. On the other hand, though, you get a stereoscopic view, definitely amazing over Jackson Hole, Wyoming. Jeff ShylukSenior Staff ReviewerAVSIM