I just updated my directx from version 9.0a to 9.0b. Before the update I was getting 30 to 40fps and now I get 3fps in the defult C172. Does anyone know how to uninstall or roll back my Directx version? Or will I need to reinstall windows?Im running Winxp Pro with SP1PJ

Run restore and u should find a restore point before the dx upgrade - thats if u use restore.

You have several options with WinXP. You can try and trouble shoot the problem to correct or you can restore to an earlier date prior to installation of DirectX9.0b. Lastly, you don't want to try and revert back manually.Try using directx diagnostic and see if you can troubleshoot your problem first. Press Start, Run..., type dxdiag, OK. Let directx diagnostic stabilize, click on each tab to ensure you don't have problems with the directx installation. On the display tab, ensure Directdraw, Direct3D, and AGP Accelerations are enable. If they are grayed out or you can't enable them, you probably need to reinstall the MOBO controller chip, i.e., Intel, VIA, SiS, AMD, ALi drivers and/or your graphics adapter drivers. If enabled, run the DirectDraw and Direct3D tests to see if they display the correct results.Check the remaining tabs and run the tests.If the above shows good results but you are still getting poor results in FS9, then reinstall directx again, followed by reinstalling the MOBO's controller chip drivers and the graphics adapter drivers.When installing updated graphics adapter drivers, it is best to uninstall the existing drivers from the Control Panel, Add/Remove Menu, if there is an entry listed for the drivers.Lastly, it is generally not a good idea to reinstall Windows each time you have these problems for the following reasons:1. You will probably lose the Windows Registry for all your installed application resulting in the reinstallation of those applications.2. You will have to reload all the MOBO controller chips, graphics adapter, sound, etc. drivers.W. Sieffert

If you need to you can always remove the DirectX runtime using this handy program: DirectX Eradicator 1.09I don't remember where I got it, but it worked great and saved my installation. Just do a search and you will find it. Works with all version of Windows.BTW, something else must be the source of your problems. I would reinstall DirectX 9.0b, plus video and sound drivers over again and I bet you will be fine.Noel

Run DXDIAG. Do you show the use of a Debug version CPL?. This will cause the performance loss you speak of. At least on my machine it reared it's ugly head. DL'ed the SDK version of DX9 and reinstalled my machine. Performance is back up to par. Just something to check.Bobby

I d/l dx9b from the Microsoft site and it too shows the use of a Debug ver.CPL. If you would'nt mind, where can I d/l the SDK ver?Regards,Russell.