Hi again all, I do hope I'm not imposing upon your knowledge and generosity too much but I have another puzzle.During answers to my previous post, it was suggested I look at a freeware program in the library here, "Reality XP Tweaker" (I think that's the right title). It was very informative and one of the pieces of information suggested that the FS9 setting "Render to texture", (I think under Hardware Rendering) isn't usually necessary. Therefore, always looking to increase efficiency on FS9 I turned it off - cleared the check box. The problem was that I could then NOT load the sim. It kept shutting down after displaying the little warning box saying there was a serious fault.I wasn't initially sure what to do but decided I'd read somewhere that you can force FS9 to rewrite the FS9 Config. program. I backed up the original and did that. Luckily the system worked again. (A good guess from me - and another tip I no doubt got from these pages:-) )To prove this was the fault I again cleared the check box on "Render to Texture" - Same fault was apparent, Sim. wouldn't load. I cleared the fault this time by just changing the line in the FS9cfg. refering to the "Render to Texture" from "0" to "1".I then used the backed up copy of FS9 Config. with the "Render to Texture" line changed in that. It worked. (I did this just to prove to myself it REALLY was this that was causing the problem.)My question is: "Can anyone tell me why this happens?" What does this "Render to Texture" actually "Do" - or what does it mean.Once again I hope someone can explain. Thanks.Regards, Blue

I can't exactly answer the question but I do know that there are a couple of types of textures (whether aircraft external paints, panels, clouds, scenery etc.) in FS9: 32-bit and DXT. To my knowledge, 32-bit is better image quality but slower while DXT yields higher frame rates but image quality is sacrificed. The catch is that if you use any DXT textures, Render to Texture must be checked (i.e. enabled). If not, various crashes (including the infamous CTD or "Crash to Desktop") can result.Given my relatively high-end set up, I stick to 32-bit textures as far as possible (if any DXT textures were installed, it would be without my knowledge as I took care to ensure that the cloud, water and aircraft repaints I installed are all 32-bit) and thus have the Render to Texture option unchecked (i.e. disabled).I think the only scenario where you MUST check Render to Texture is if you use DXT textures. If using 32-bit textures, I think it should work either way but I haven't verified. Nor have I tested to see whether there are any visual or performance differences between checking and unchecking that option. All I can say is that I use 32-bit and have the setting unchecked and am not encountering any strange crashes.Hope this helps.Edwin

Edwin, thanks for your reply. Indeed I did get a CTD at the start of the fault. Basically I was at KSEA with the default Caravan (doing another test run as previous post described to compare frame rates) - I went into the menu and UNCHECKED the "Render to Texture" setting. On going back into the Sim. (an outside view I believe - or when back in the Sim I switched to an outside view) bang! CTD.Thereafter when it tried to reload the Sim. the warning box came up with the option "send" / "Don't send". I cancelled the box but the Sim just would not complete the load - it carried on loading for a few seconds before CTD again. I tried resetting the Computer and the Sim. but each time I tried to reload - same problem.I cleared it as already explained. I don't know if this fits in with your explanation as I don't know much about the various "Texture" types, ie which are 32 bit and which arn't. Indeed, truth to tell, I don't know what 32 bit even means, although I've seen the expression and appreciate it is describing a "good" or "detailed" model. (I think:-) )Regards, Blue