I know with XP 64 bit you had to enter /3GB switch so that windows would access more RAM while using FS9, does vista 64-bit require a similar modification while running FS9? If so, how do you make the modification?ThanksRich PerryIntel i7 965 Extreme 3.2GhzOCZ 6 GB DDR3 RAM 1800MhzNvidia GTX 285 2GB GPUVel Raptor 300GB SATA HD 10000rpmSB Xi-ExtremeDell 24 1920x1200Windows Ultimate 64-Bit

I know with XP 64 bit you had to enter /3GB switch so that windows would access more RAM while using FS9, does vista 64-bit require a similar modification while running FS9? If so, how do you make the modification?ThanksRich PerryIntel i7 965 Extreme 3.2GhzOCZ 6 GB DDR3 RAM 1800MhzNvidia GTX 285 2GB GPUVel Raptor 300GB SATA HD 10000rpmSB Xi-ExtremeDell 24 1920x1200Windows Ultimate 64-Bit

I think it depends on the aircraft as to how much RAM FS9 would use. I have Vista 64 and a machine (Quad 8200) and video card (9500 1GB SPU) at a lower spec than yours, and haven't had to make any tweaks or mods to enjoy FS9 at its fullest. Regards,John

I know with XP 64 bit you had to enter /3GB switch so that windows would access more RAM while using FS9, does vista 64-bit require a similar modification while running FS9? If so, how do you make the modification?ThanksRich PerryIntel i7 965 Extreme 3.2GhzOCZ 6 GB DDR3 RAM 1800MhzNvidia GTX 285 2GB GPUVel Raptor 300GB SATA HD 10000rpmSB Xi-ExtremeDell 24 1920x1200Windows Ultimate 64-Bit

No, all 64-bit Windows OSs give all programs 4 GB of space to work in--IF the LARGEADDRESSAWARE flag is set in the program executable's header. So Vista 64 needs nothing done to it (the /3GB switch is only for 32-bit Windows XP/Vista), but FS9.exe does need to be modified to enable it to use RAM addresses above the 2GB limit that is standard for 32-bit programs.A search here for LARGEADDRESSAWARE should yield several how-tos on the mod. Also, FSX with SP2 and/or acceleration already has the LARGEADDRESSAWARE flag set as part of the service pack changes.CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

No, all 64-bit Windows OSs give all programs 4 GB of space to work in--IF the LARGEADDRESSAWARE flag is set in the program executable's header. So Vista 64 needs nothing done to it (the /3GB switch is only for 32-bit Windows XP/Vista), but FS9.exe does need to be modified to enable it to use RAM addresses above the 2GB limit that is standard for 32-bit programs.A search here for LARGEADDRESSAWARE should yield several how-tos on the mod. Also, FSX with SP2 and/or acceleration already has the LARGEADDRESSAWARE flag set as part of the service pack changes.BobI found your post and made the changes within XVI32--the editor worked like a charm. However, when I click on the FS9 icon to start, it gives me an error saying: C:\FS9\fs9.exe is not a valid Win32 applicationI went into Explorer Suite and made sure: fs9.exe is hi-mem enabled, you need CFF Explorer http://www.ntcore.com/exsuite.php - File Header / Click Here / App can handle >2GB... checked. Rich

BobI found your post and made the changes within XVI32--the editor worked like a charm. However, when I click on the FS9 icon to start, it gives me an error saying: C:\FS9\fs9.exe is not a valid Win32 applicationI went into Explorer Suite and made sure: fs9.exe is hi-mem enabled, you need CFF Explorer http://www.ntcore.com/exsuite.php - File Header / Click Here / App can handle >2GB... checked. Rich

I'm guessing you're either using the original FS9.0 version, or an otherwise modified FS9.exe (no-CD hack, processor affinity mask modification etc) . The byte editor changes only work on the original FS9.1 executable.You can also make the change with Explorer Suite without doing the byte edits. I don't know the nitty gritty...I use a utility that comes as part of the Visual Studio programming suite to make the changes. I know I read a post on how to do it with Explorer Suite here recently.CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

I know with XP 64 bit you had to enter /3GB switch so that windows would access more RAM while using FS9

According to Microsoft, you don't: "...even 32-bit applications will benefit from increased virtual memory address space when running in Windows x64 Editions. Applications that are compiled with /LARGEADDRESSAWARE, which would be required to use the /3GB switch in 32-bit Windows, will automatically be able to address 4 GB of virtual memory without any boot time switches or changes to x64 Windows. Plus, the operating system does not have to share that memory, so it is not constrained in the same way an application running in a 32-bit environment might be."http://enterprise.amd.com/downloads/MSWindows64_en.pdf

I'm guessing you're either using the original FS9.0 version, or an otherwise modified FS9.exe (no-CD hack, processor affinity mask modification etc) . The byte editor changes only work on the original FS9.1 executable.You can also make the change with Explorer Suite without doing the byte edits. I don't know the nitty gritty...I use a utility that comes as part of the Visual Studio programming suite to make the changes. I know I read a post on how to do it with Explorer Suite here recently.CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

BobI've got the right version of FS9.1 exe loaded (9.1.040901)--the basic question I have is: do I need to only do the changes you suggested within XVI32? Or, is there some other cosmic line I need to modify in the header etc?ThanksRich

http://ntcore.com/4gb_patch.phpUse his simplified tool there for patching it to see beyond 2GB....

http://ntcore.com/4gb_patch.phpUse his simplified tool there for patching it to see beyond 2GB....

Thanks...I used CFF explorer (part of ntcore package I think) and opened up FS9.exe and added to the Header (click)...checked the box "allow app to use >2GB"....and saved (overwrote) current FS9.exe....worked fine.Rich Perry