Sorry to raise this hairy topic again but I am having OOM difficulties in FS2004 (ver 9.1 installed) and therefore have tried to enable the 3GB switch in Win XP Proffessional (32 Bit). I have followed the instructions in these two discussion threads http://www.simforums...topic24500.html http://flightsimavia...oom-errors.html but windows fails to boot when using the Operating System choice with the 3GB line in it. I have an Nvidia GeForce 9800GTX/9800GTX+ and used Userva = 2560. (I have also patched the FS9.exe file appropriately but this is academic at the moment!) I have read that there might be a problem with one or other of my drivers but looking at them in Device Manager the Digital Signer is either: "Microsoft Windows Component Publisher", or "Microsoft Windows Hardware Compatibility Publisher", so as far as I can see, all these drivers are windows compliant. Does anybody have any thoughts as to why I cannot boot up Windows with the 3GB switch enabled in the Boot.ini file or which driver might be "favorite" as the offending one? ThanksJohn

Sorry to raise this hairy topic again but I am having OOM difficulties in FS2004 (ver 9.1 installed) and therefore have tried to enable the 3GB switch in Win XP Proffessional (32 Bit). I have followed the instructions in these two discussion threads http://www.simforums...topic24500.html http://flightsimavia...oom-errors.html but windows fails to boot when using the Operating System choice with the 3GB line in it. I have an Nvidia GeForce 9800GTX/9800GTX+ and used Userva = 2560. (I have also patched the FS9.exe file appropriately but this is academic at the moment!) I have read that there might be a problem with one or other of my drivers but looking at them in Device Manager the Digital Signer is either: "Microsoft Windows Component Publisher", or "Microsoft Windows Hardware Compatibility Publisher", so as far as I can see, all these drivers are windows compliant. Does anybody have any thoughts as to why I cannot boot up Windows with the 3GB switch enabled in the Boot.ini file or which driver might be "favorite" as the offending one? ThanksJohn

Perhaps if you were to copy and paste the contents of your Boot.ini file? DJ

I did that. I copied and pasted the original OS line and then added the 3GB switch line to that. I edited the boot.ini file by using "My Computer" - "Properties" - "Advanced" - "Start-up and Recovery" - "Settings" - "Edit". The Boot.ini file looks like this now: [boot loader]timeout=30default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS[operating systems]multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows XP Professional" /noexecute=optin /Fastdetect (This OS boots ok.)multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /3GB /Userva=2560 (This OS Fails to boot). When booting with the second OS, windows starts but soon after I get the "blue screen of death" for about a quarter of a second or less (certainly not enough to read anything) and then the system re-boots and I have to select the alternative OS. RegardsJohn

I did that. I copied and pasted the original OS line and then added the 3GB switch line to that. I edited the boot.ini file by using "My Computer" - "Properties" - "Advanced" - "Start-up and Recovery" - "Settings" - "Edit". The Boot.ini file looks like this now: [boot loader]timeout=30default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS[operating systems]multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows XP Professional" /noexecute=optin /Fastdetect (This OS boots ok.)multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /3GB /Userva=2560 (This OS Fails to boot). When booting with the second OS, windows starts but soon after I get the "blue screen of death" for about a quarter of a second or less (certainly not enough to read anything) and then the system re-boots and I have to select the alternative OS. RegardsJohn

I don't see anything wrong with the syntax... have you tried booting into safemode with the 3GB enabled? If it succeeds then you have a driver issue, and will have to track it down. You might also try reducing userva to 2280 (gives you 2.5 Gb) to see if there is just no room for a driver. In the end, if your system can run it, I would recommend going to a 64 bit OS. DJ

Tried booting in safe mode with 3GB enabled - but still failed. At a loss now!! RegardsJohn

What's in your start up folder? Also run msconfig and see what's starting when windows start. You can then shut down all the startup programs, then try to re boot the OS you're having issue with. If you're able to boot then you need to enable each program in start up to see what's crashing. Hpoe this helps.