Regarding memory for PMDG

[Biku 3]

Hi Guys Hope you are doing great. i got ask you guys although its quite out of topic for to post this in forum. i had isssue that i play pmdg 737ngx and some of the scenery loads require huge memory like VFR London. from aerosoft . i fly pmdg 737ngx with wing view its reallly really great fell like you are there. hehe. but the problem suddenly it shows out of memory or sometimes it lags. although my memory is 12gb 1400Mhz . when i restart my memory display only 8gb the rest 12gb is no more there but physical there are.. do you know guys how to get rid of this problem . Thank youBikash kc

[sam086 0]

If i remember reading correctly in a previous thread, fsx only utilizes 3gb of memory, so regardless of how much ram you have, you wont see any improvements, i'm not sure about your other problem though.

[NGX 1]

Regarding your system only showing 8GB instead of 12. I'm going to guess you have 3 4GB sticks. One of them is faulty. As for the OOM, use a 64bit OS. OOMs have nothing to do with how much ram you have. It's all to do with the virtual address space. The best fix for this is using Windows 7 64bit as it manages memory better and the 64bit will use the extra ram

[Tabs 2,790]

FSX.exe is a 32-bit app - it has a 4GB maximum virtual address space limit, that's it. Your video card memory is part of that 4GB limit too, so it's actually quite easy to get into the OOM situation with a big 2GB card or multiple smaller cards.

[realpilotsimpilot 11]

Ryan, weren't you going to do a memory best practices post for the NGX? Is that still forthcoming? Would you care to update your original estimate of last Monday?

[Tabs 2,790]

We're still investigating - we don't want to say anything "official" on the subject until we're positive. This is straight out of the Direct3D SDK though: "If an application creates its own in-memory copy of its video resources, or the application uses DirectX 9 or an earlier version, the virtual address space contains the WDDM video memory manager's virtualized range and the application's copy. Applications that use graphics APIs that are earlier than DirectX 10 and that target GPUs that have large amounts of video memory can easily exhaust their virtual address space."

[realpilotsimpilot 11]

Interesting, thanks. So, does this mean that switching to "DX10 Preview Mode" could help? I was under the impression the DX10 mode was kind a of bad idea for most FSX add-ons.

[Tabs 2,790]

It's possible yes - it has its own set of issues, but virtual address space exhaustion as a result of video memory shouldn't be one of them.

[realpilotsimpilot 11]

Interesting. Maybe I'll play with that. I know some sceneries aren't DX10 Compatible (most FlyTampa and all FSDT, for instance), so that's something to think about too.