Hello ThereI recently purchased a New PC from Jetline Systems ( acompany that builds PC for Simulation) with Windows Vista 64Bit, 7i dual core processor, Nvidia 1 GB Ram and 6 GB RAMFSX runs fine with many addon e.g. Activesky, LDS767, PMDG747, and Ultimate traffic etc.However, more often than I expect, FSX freezes up running out of Memory. It does not crash but freezes up.Upon checking Task manger, I see FSX runs fine as long as it claims 1.2GB of RAM.When it is under 1Gb that is when it freezes up. I close some processes and applications running in the background and I can resume flying.My questions are: How does FSX access the memory bank in Vista 64Bit?Can I allocate say 2GB or more of the 6GB to FSX, and How?because even with other applications and processes are running, it does not add to 6GBAny help will be greatly appreciatedBill

My questions are: How does FSX access the memory bank in Vista 64Bit?Can I allocate say 2GB or more of the 6GB to FSX, and How?because even with other applications and processes are running, it does not add to 6GBAny help will be greatly appreciatedBill

I'm not a memory guru for sure but here's a link to a post with a similar question from an individual who had a 64 bit Vista system like yours and was receiving OOM's. Appears FSX is a 32 bit application and 64 bit users need to allocate virtual memory just like 32 bit users w/the /3GB switch for XP users and the BCDEdit increaseuserva switch for Vista users: http://forums1.avsim.net/index.php?showtopic=249474. And here's a link to an excellent discussion on tuning FSX by NickN: http://www.simforums.com/forums/forum_posts.asp?TID=29041. Hope these links help in sorting out your issue!Best regards,Jim Young

I'm not a memory guru for sure but here's a link to a post with a similar question from an individual who had a 64 bit Vista system like yours and was receiving OOM's. Appears FSX is a 32 bit application and 64 bit users need to allocate virtual memory just like 32 bit users w/the /3GB switch for XP users and the BCDEdit increaseuserva switch for Vista users: http://forums1.avsim.net/index.php?showtopic=249474. And here's a link to an excellent discussion on tuning FSX by NickN: http://www.simforums.com/forums/forum_posts.asp?TID=29041. Hope these links help in sorting out your issue!Best regards,Jim Young

I'm not a memory guru for sure but here's a link to a post with a similar question from an individual who had a 64 bit Vista system like yours and was receiving OOM's. Appears FSX is a 32 bit application and 64 bit users need to allocate virtual memory just like 32 bit users w/the /3GB switch for XP users and the BCDEdit increaseuserva switch for Vista users: http://forums1.avsim.net/index.php?showtopic=249474. And here's a link to an excellent discussion on tuning FSX by NickN: http://www.simforums.com/forums/forum_posts.asp?TID=29041. Hope these links help in sorting out your issue!Best regards,Jim Young

Hello JimThank you so much for the prompt response, the information and link. Going through Nick's link it seems that is very helpful. Time to dig in.Best RegardsBill Hagag

Hello ThereI recently purchased a New PC from Jetline Systems ( acompany that builds PC for Simulation) with Windows Vista 64Bit, 7i dual core processor, Nvidia 1 GB Ram and 6 GB RAMFSX runs fine with many addon e.g. Activesky, LDS767, PMDG747, and Ultimate traffic etc.However, more often than I expect, FSX freezes up running out of Memory. It does not crash but freezes up.Upon checking Task manger, I see FSX runs fine as long as it claims 1.2GB of RAM.When it is under 1Gb that is when it freezes up. I close some processes and applications running in the background and I can resume flying.My questions are: How does FSX access the memory bank in Vista 64Bit?Can I allocate say 2GB or more of the 6GB to FSX, and How?because even with other applications and processes are running, it does not add to 6GBAny help will be greatly appreciatedBill

64 bit operating systems do not require the use of the /3GB switch. The use of /3GB switch is reserved 32 bit systems running FSX. If you are running SP2 or Acceleration the Fsx.exe comes modified so that it can utilize what ever memory it needs on a 64 bit system (or more than 2MB ON a 32 bit system using the /3GB switch). FSX is only going to use what it needs. Which means under a 64 bit OS you do not need to allocate any additional memory to FSX. As with any OS, when running FSX, it is advised to shutdown any background applications and run only FSX and its supporting applications (such as REX or ASA etc..). If you notice that closing background applications allows you to resume flight, then you have found that your background application is what is causing your system hang. Just because you have 6GB does not mean that you will utilize all of it nor does it mean if your not utilizing all of it that you are safe from running into problems. Again, as already said, only run FSX and its supporting applications and close any unecessary applications.Regards,Bob

64 bit operating systems do not require the use of the /3GB switch. The use of /3GB switch is reserved 32 bit systems running FSX. If you are running SP2 or Acceleration the Fsx.exe comes modified so that it can utilize what ever memory it needs on a 64 bit system (or more than 2MB ON a 32 bit system using the /3GB switch). FSX is only going to use what it needs. Which means under a 64 bit OS you do not need to allocate any additional memory to FSX. As with any OS, when running FSX, it is advised to shutdown any background applications and run only FSX and its supporting applications (such as REX or ASA etc..). If you notice that closing background applications allows you to resume flight, then you have found that your background application is what is causing your system hang. Just because you have 6GB does not mean that you will utilize all of it nor does it mean if your not utilizing all of it that you are safe from running into problems. Again, as already said, only run FSX and its supporting applications and close any unecessary applications.Regards,Bob

Bob, did you read the AVSIM forum link I posted above before posting? According to that link, you are wrong. I wish we wouldn't continue to confuse everyone. You're even confusing me! :( It is important to note in the forum link I posted, NickN states people with 64bit systems not having OOM issues DO NOT need to apply these switches. Best regards,Jim Young

Bob, did you read the AVSIM forum link I posted above before posting? According to that link, you are wrong. I wish we wouldn't continue to confuse everyone. You're even confusing me! :( It is important to note in the forum link I posted, NickN states people with 64bit systems not having OOM issues DO NOT need to apply these switches. Best regards,Jim Young

Jim,Please reread Nick's post if you think that I am wrong. I think you you may be misinterpreting something in his post. 64 bit systems DO NOT need the switch as they can address any of the memory installed if the system is requesting it up to 128GB (32 bit systems support a maximum of 4GB of RAM). 64 bit systems manage memory entirely different than do 32 bit systems. Also the AVSIM post you referenced also supports what I posted. SP1 is not large address aware and SP2 is. If one runs SP1 on Vista X64 and has OOM's all they need to do is mark the FSX.exe large address aware as Nick described in the post. I agree last thing we need is more confusion. :( From Nick's guide:USING MORE/LESS or EQUAL to 2GIGS OF SYSTEM MEMORY IN WINDOWS XP x32 OR VISTA X32 with OOM-OR-HOW TO PROPERLY TUNE VIRTUAL ADDRESS SPACE IN WINDOWS (x32) FOR OUT OF MEMORY ERRORS x64 operating systems do not need the following changesRegards,Bob Modrowski

NickN states people with 64bit systems not having OOM issues DO NOT need to apply these switches. Best regards,Jim Young

Talk about confusing... :) there's a double negative. Does that imply that 64bit users who ARE having OOM issues SHOULD apply the switches? I hope no one interprets it that way because they would be dead wrong. As Bob said - the /3G switch is USELESS in a 64 bit OS. If and that's *IF* you are NOT running SP2 or Acceleration, you need to make FSX large address aware but if you ARE running SP2 you don't need it, and frankly, you wouldn't be able to do it anyway. If you have a 64bit OS AND are having OOM problems, you have other stuff running that's causing issues or you might have some bad memory but nothing having to do with the /3G switch.There, does that eliminate some confusion? :( Vic

Talk about confusing... :) there's a double negative. Does that imply that 64bit users who ARE having OOM issues SHOULD apply the switches? I hope no one interprets it that way because they would be dead wrong. As Bob said - the /3G switch is USELESS in a 64 bit OS. If and that's *IF* you are NOT running SP2 or Acceleration, you need to make FSX large address aware but if you ARE running SP2 you don't need it, and frankly, you wouldn't be able to do it anyway. If you have a 64bit OS AND are having OOM problems, you have other stuff running that's causing issues or you might have some bad memory but nothing having to do with the /3G switch.There, does that eliminate some confusion? :( Vic

Vic,LMAO...... :( You just made my day!!-Bob

I agree with all wrt 64-bit systems not needing the /3GB or the /USERVA switch. It may cause a whole heap of problems if you applied it to Vista64Actually the original poster's statement doesn't really state what the error message that he gets: "FSX freezes up running out of Memory. It does not crash but freezes up"What is the OOM error that he sees is it really an OOM error or a videocard driver issue or some other hardware/software conflict. We all know that FSX freezes up in all sorts of systems and Os's.It could even be a simconnect or WinSxS issue.I would like to see the the actual error message that is displayed when the application freezes.RegardsPeterH

My pc also has 6 Gb of memory and I am using ASA, UT US/EU, many scenery , REX , FsWaterconfigurator, PMDG MD-11 , MT etc etc.When flying with FSX there is always more than 2 Gb memory left.If you have less than 1 Gb left than there is something defenitely not right.Perhaps a memory leak because of a scenery with ( landclass ) errors.If you are having this only lately ask yourself what you have added to FSX.

I'm not a memory guru for sure but here's a link to a post with a similar question from an individual who had a 64 bit Vista system like yours and was receiving OOM's. Appears FSX is a 32 bit application and 64 bit users need to allocate virtual memory just like 32 bit users w/the /3GB switch for XP users and the BCDEdit increaseuserva switch for Vista users: http://forums1.avsim.net/index.php?showtopic=249474. And here's a link to an excellent discussion on tuning FSX by NickN: http://www.simforums.com/forums/forum_posts.asp?TID=29041. Hope these links help in sorting out your issue!Best regards,Jim Young

You need to RE READ that entire thread.. Bill removed his references to the suggestion a 64bit OS will make use of any USERVA edit The OP in that thread I worked with in the hardware forum and we corrected his issues which were a combination of defective video card and over the top TWEAKS in the FSX.cfg file he was using to try and overcome the wrong purchases in system memory and problems with his video card. After he swapped out the video card, purchased the RIGHT memory and set it up the RIGHT way in the BIOS and after getting his FSX.cfg file tuned correctly all his OOM issues ceasedNow, please read this carefully about OOM and a 64bit OS:

No, it does not sound oddLets all back up a minuteI never defined the OOM error as: "OVERCLOCKING CAUSED OOM"1. The OP

Vic,LMAO...... :( You just made my day!!-Bob

Sometimes you just call 'em as you see 'em.:)

You need to RE READ that entire thread.. Bill removed his references to the suggestion a 64bit OS will make use of any USERVA edit The OP in that thread I worked with in the hardware forum and we corrected his issues which were a combination of defective video card and over the top TWEAKS in the FSX.cfg file he was using to try and overcome the wrong purchases in system memory and problems with his video card. After he swapped out the video card, purchased the RIGHT memory and set it up the RIGHT way in the BIOS and after getting his FSX.cfg file tuned correctly all his OOM issues ceasedNow, please read this carefully about OOM and a 64bit OS:

Nick, thanks for the update and info. I hope this ends the confusion surrounding OOM's in 64bit OS's but I doubt it....Best regards,Jim Young

Hello ThereI recently purchased a New PC from Jetline Systems ( acompany that builds PC for Simulation) with Windows Vista 64Bit, 7i dual core processor, Nvidia 1 GB Ram and 6 GB RAMFSX runs fine with many addon e.g. Activesky, LDS767, PMDG747, and Ultimate traffic etc.However, more often than I expect, FSX freezes up running out of Memory. It does not crash but freezes up.Upon checking Task manger, I see FSX runs fine as long as it claims 1.2GB of RAM.When it is under 1Gb that is when it freezes up. I close some processes and applications running in the background and I can resume flying.My questions are: How does FSX access the memory bank in Vista 64Bit?Can I allocate say 2GB or more of the 6GB to FSX, and How?because even with other applications and processes are running, it does not add to 6GBAny help will be greatly appreciatedBill

I suspect what you are experiencing is due to the fact that you have not installed the two service packs for FSX.My system is pretty much like yours i7920 nvdia 1 gig card vista 64.and the only time i ever get those out of memory issues is when the service packs are not installed correctly.Plus FSx should be using way more than 1.2gig if you have 6 gig installed, on my system FSX uses anything up to 4.2 gigs of ram.if you already have them installed, uninstall SP2, then start FSX, and launch a flight to complete the uninstall.then 1 - install SP1 and its SDK start FSX flight2 - install PS2 and its SDK then start a flightDont just install SP1 and SP2 without loading a FSX then a free flight in between the service pack installations.