i was one of many people suffering from out of memory messages and crashes to desktop at the end of long flights.that was until i modified my pc to a dual boot system using the 3 GB switch.now the OOM & CTD have gone.but we dont live in perfect world.when i start my pc with this modification and start fs9 ive lost the textures on the level-d 767-300 & pmdg 737-800ng.im using the pmdg 747-400 Queen of the skies for long hauls and the textures are okay.but i might want to use level-d 767-300 for a long flight and then what?ive got the latest drivers for every thing.so ive got the 3GB switch,the autogen file in fs9 renamed to autogen.passive.System Specs---intel E6850 dualcore 4GB kingston ram leadtek 8800gts 320 winxp pro sp2 twin sata hds x-fi sound card.when i boot into winxp pro normally and run fs9 the textures are ok.any advice greatly appreciated

Try adding/userva=2560after the /3GB if it's not there already.

thanks for the quick reply ryan.but i got this info about the 3GB switch on simforums and they where talking about video cards with 512megs and above so i didnt add the extra part/userva=2560.mine is only 320megs

Not sure what to tell you then man, sorry. I've had trouble with /3GB before as well, it was causing crashes and stuff in other games besides FS. I really think Vista 64 is ultimately gonna have to be the solution...

I agree. We're really pushing the envelope of this 32bit op system. It's really gonna be "a messy transition."http://www.anandtech.com/gadgets/showdoc.aspx?i=3034&p=4

well i added the extra line to the boot.ini /Userva=2560 and the missing textures returned.i booted twice just to make sure.thanks for the advice guys--happy flying

I have a question about this task and problem, If you run only 3 GB am RAM on your PC will you be ale to set 3GB for FSX or FS9or do you have to actualy have more then 3GB to do it?Thank YouCapt. Eric Wade Joneswww.usairwaysva.orghttp://www.precisionmanuals.com/images/forum/pmdg_trijet.jpg

Hi,1) 32-bit operating systems do not have the address lines to address 4Gb of memory and all the hardware (it is memory mapped I/O).2) The /3Gb switch is a hack, and whilst MS and others may suggest its use, its use is ILL ADVISED. It causes other parts of Windows to run shorter on memory than normal, and certain sub-systems (such as DirectX) actually CRASH in this config as it does NOT know how to deal with memory over 2Gb!!!The best thing you could do for FSX is to get a 64-bit OS. Whilst Vista has its problems even with SP1, I have NO ISSUES AT ALL with FSX under Vista 64-bit.The whole way the memory architecture works under a 64-bit OS is fundamentally different to the way it works under a 32-bit OS.I know you probably didn't want to hear this, but there is nothing any of us can do about it. The bottom line is we're pushing 32-bit OS to the limits and beyond on memory usage, and it's breaking it.** NOTE THAT YOU REQUIRE 64-BIT CAPABLE HARDWARE TO RUN A 64-BIT OS!! **May I suggest a sticky regarding this issue? This problem is only set to get worse as we load our sims with more scenery and aircraft add-ons.Best regards,Robin.

We are setting switches for the op system's memory prediction notepad. Not for physical memory usage. Since this prediction notepad always runs higher than physical memory usage, the system will OOM before the physical memory "fills up." There are 2 switches. One is in the FSX.exe/FS9.exe file and the other is in the op systems kernal. FSX's SP2 set the switch in the FSX.exe file. It must be set manually for the FS9.exe file. The second switch in the op system's kernal must be set manually. I entirely agree this is Not an optimum solution. However for a 32bit user, it's their Only solution.

Hi Guys.Please take a look at my post - I had the same /3GB issue and nVidia card:http://forums.avsim.net/dcboard.php?az=sho...id=156762&page=Now without /3gb switch problem has gone. Do you think is VISTA 64-bit with FSX + PMDG 747&MD-11 stable and efficient?Regardsczarek

Of course, Vista 64 does not need this switching. It is already setup to allow 4G on its memory prediction notepad. Vista 64 is the way to go if at all possible. It will provide the most stable and trouble free platform. However . . . If one is having problems with a 3G switched 32bit system,"Try adding/userva=2560after the /3GB if it's not there already.Ryan Maziarz"This fine tunes a 32bit op system's memory prediction notepad to only allow 2.56Gs onto its little talley sheet, rather than the full 3Gs. It might help. Again, this is Not about physical ram. We're tweaking internal processes that are occurring within the op system's "kernal."

Thx Sam.About one year ago when I bought PMDG 747 it was recommended to not use FSX on Vista (32bit) due to stability problems (OOM, etc.); so I choose XP.Am I right Vista 64bit with SP1 provide sufficient stability for PMDG planes on FSX?RegardsCzarek

Yes. Vista 64/SP1 is the operating system to use. PMDG is blazing this trail toward our inevitable future. As far as any inconvenience with drivers for that old USB drive, etc . . . it's really a matter of 'pay me now, or pay me later.' All big games will need 64bit's elbow room soon. We're just leading the way. Ain't it grand? (Not!)

Sam,Yesterday I installed Vista 64-bit and I have to say I am really positively suprised:) All 4GB can be used, no CTD or OOM... In MD-11 VC I have 20-40 FPS (with default scenery for now :) Let's see what happends with sophisticated scenery addons...R.czarek