I kind of question this whole thread. As far as RAM, on a 64 bit system any RAM that is masked by hardware in the system address space is going to be remapped. As far as process address space, or VAS if you will, what I remember from Phil Taylor was that in FSX RTM they were storing FSX video memory copy in process address space AND the OS was storing it in the "upper 2Gb" address space reserved to the OS (or "upper 1 Gb" if /3GB set) . However what I recall is he said they got rid of that local copy in IIRC SP2. So on a x64 OS, all the video memory space for FSX is in the OS managed memory that is above the 4Gb that FSX gets.If I'm right then having large and/or SLI/Crossfire video RAM should not make a difference from an FSX process address space perspective (on x64 OS). scott s..

In FSX + a 64b OS "the upper 2GB (or "upper 1 Gb" if /3GB set)" doesn't apply, cause FSX is Large Address Aware, so it has 4GB for itself.However I think you are right and FSX doesn't use much VRAM in it's address space if any at all.

I am quite sure you guys are right. I am yet to see any proof that the VRAM is being stored in those 4gb...

Hello guys,I just found this thread while searching for any proof that "VideoMemoryOverride=n" is doing anything in reality. The only hint, that something might be eating parts of the 4G being allocated for applications by 64bit systems is the fact that I'm always in trouble when the memory use reaches the magic border of about 3.4GByte. I can wait in those cases for OOM errors while flying in a dense scenery (e.g. AI traffic) and with a demanding model like PMDG's NGX. There is indeed some evidence that your suspiciousness is qualified as if anybody could even fly a mile with a 3G video adapter while the sim just could use the remaining 1GByte would surprise me. However, because of my experienced OOM errors I got answers from PMDG's support telling me about the video RAM mapping being part of the overall 4G address space. I even thought about down-scaling my system with an old 512k GPU card.

For a 1.5 GB the line would be[DISPLAY.Device.NVIDIA GeForce GTX 580.0]Mode=1920x1080x32VideoMemoryOverride=1610612736

The main question for me remains: What are those settings good for in fsx.cfg???? :Confused:

Edited January 16, 201214 yr by FlyingAxx

I don't understand what you have with "GPU usage in FSX is bad"? Mine is mostly around 80-90%. Maybe at times 60%...

Edited January 16, 201214 yr by Kosta

Hello guys,I just found this thread while searching for any proof that "VideoMemoryOverride=n" is doing anything in reality. The only hint, that something might be eating parts of the 4G being allocated for applications by 64bit systems is the fact that I'm always in trouble when the memory use reaches the magic border of about 3.4GByte. I can wait in those cases for OOM errors while flying in a dense scenery (e.g. AI traffic) and with a demanding model like PMDG's NGX. There is indeed some evidence that your suspiciousness is qualified as if anybody could even fly a mile with a 3G video adapter while the sim just could use the remaining 1GByte would surprise me. However, because of my experienced OOM errors I got answers from PMDG's support telling me about the video RAM mapping being part of the overall 4G address space. I even thought about down-scaling my system with an old 512k GPU card.The main question for me remains: What are those settings good for in fsx.cfg???? :Confused:

can you please upload your fsx.cfg?VideoMemoryOverride doesn't seem to limit the amount of VRAM usage as monitored in MSI afterburner. Using a VRAM intensive AA mode like 64X_4v12 I often see my VRAM usage go above 1GB, even with a 512MB VideoMemoryOverrideVAS usage in FSX is unaffected too.I really have no idea what's going on. I never have OOM's unless I push my LOD to 6.5 at ORBX PNW in the NGX with sliders cranked up, or something crazy like that

Oops, beside the fact that I made the (proposed???) graphic memory 10^3 times smaller than it should, I usually don't have really problems any more with OOMs since I down-scaled my UT2 traffic to 30% of its full capability. I did not monitor my VRAM usage either, only the main memory consumption which might (!) include VRAM usage as well - if PMDG's support is right.However, you could PM me with your email address as this forum does not allow to upload CFG files nor ZIPs. I would appreciate any help in this case.

Oops, beside the fact that I made the (proposed???) graphic memory 10^3 times smaller than it should, I usually don't have really problems any more with OOMs since I down-scaled my UT2 traffic to 30% of its full capability. I did not monitor my VRAM usage either, only the main memory consumption which might (!) include VRAM usage as well - if PMDG's support is right.However, you could PM me with your email address as this forum does not allow to upload CFG files nor ZIPs. I would appreciate any help in this case.

Well, it's more like the other way around: RAM usage is a subset of the app's VAS. If you are hitting 3.4GB of RAM usage in FSX then it's VAS usage is going to be very close to the dreaded 4GB limit.You can upload your cfg file if you change the extension to pdf, which I believe is the only format allowed

Well, it's more like the other way around: RAM usage is a subset of the app's VAS. If you are hitting 3.4GB of RAM usage in FSX then it's VAS usage is going to be very close to the dreaded 4GB limit.You can upload your cfg file if you change the extension to pdf, which I believe is the only format allowed

Ok Dario, I think I'll have to deal with this one day...The renamed config file is attached. Some manual changes I commented but no guaranty, though. The only thing I deleted is the last multiplayer related section. I would be highly interested to know why some do have OOM issues and others (like you) not.BTW, I did not find any comprehensive (complete would be even better) documentation of the keywords being used in the FSX.CFG. There are just lists of the usual tweaks. Do you know sources?

Ok Dario, I think I'll have to deal with this one day...The renamed config file is attached. Some manual changes I commented but no guaranty, though. The only thing I deleted is the last multiplayer related section. I would be highly interested to know why some do have OOM issues and others (like you) not.BTW, I did not find any comprehensive (complete would be even better) documentation of the keywords being used in the FSX.CFG. There are just lists of the usual tweaks. Do you know sources?

I'm testing your cfg now. Would you like to talk in Skype, maybe a remote session with Teamviewer and run some tests to see what's starvating your memory?

I'm testing your cfg now. Would you like to talk in Skype, maybe a remote session with Teamviewer and run some tests to see what's starvating your memory?

Dario, if you want we could try a contact via Skype. I think I found you and have send a request.Cheers,Axel