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psolk

How does PMDG feel about this?

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As I had mentioned a while back FSX is plagued with OOM errors even in the default sim. Now it looks like Phil Taylor has acknowledged that both FS9 and FSX are plagued by this issue. http://forums.avsim.net/dcboard.php?az=sho...id=399256&page= Yes, MS wrote two sims that just like their Exchange Server can not even stay within the limitations of the O/S they run on. Phil has also said they will not modify either version of FS to stay within the limits of the O/S. In fact what they are telling people is to apply the /3GB switch to XP Pro and Vista to eliminate the issue. Well anyone running high memory video cards can not do this. It does not leave enough memory for the O/S and the card and you start losing things like AA/AF.So I was just wondering what your thoughts were now that years of fighting the OOM comes down to a poorly written app that MS is not going to fix but instead recommend a tweak that is not even viable for most...I know I am more than a little disturbed and disappointed but wanted to get the professionals opinion.-PaulPrimary RigLiquid CooledIntel C2D E6600 @3.2 gigsAsus P5N32SLI-Plus2 gigs Corsair XMS PC6400 4 4 4 12 @810Dual OC'd XFX 8800GTX @ 2 gigs24 inch Widescreen LCD 16XAA/16XAFDual 19 inch LCD'sRaid-0+1PCPower and Cooling 1k Quad SLIhttp://home.comcast.net/~psolk/3monitorsa.htmlBackup RigAMD 4000 San Diego @ 2.72 Gigs Kingston Corsair XMS CL2XFX 7900 GTX Raid-0psolk.jpg

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Paul-there's more to this story though than what you describe. Phil posted a note in his blog here:http://blogs.msdn.com/ptaylor/archive/2007...ress-space.aspxI recommend that everyone concerned with this issue thoroughly read it first, then draw their own conclusions regarding whether adding the /3GB switch is an issue any longer.

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Thanks Lefteris,Even Phil states that this needs to be used with care:"Note this switch needs to be used with care, since PCI-Express maps the entire address space of the graphics card into the OS address space. If you set the app to use 3G with a 768m graphics card, that leaves 256m for the OS. A better setting is 2560, eg 2.5G, since that leaves 768m for the OS with a 786m graphics card. Much more reasonable."So now a lot of us who are starting to run dual 768 meg video cards really can't use this proposed fix at all. And what happens when we start to see 1 gig video cards? I just think it would be more appropriate of Phil and the team to limit FS to the low memory space reserved for the app in the first place rather than asking the user to access memory space that was really designed to be reseverd expect on servers. TBH, MS wrote a 32 bit app that exceeeds the 32 bit memory limitations just like MS did with Exchange server and they are putting the "fix" off on the end user. Just my .02,-PaulPrimary RigLiquid CooledIntel C2D E6600 @3.2 gigsAsus P5N32SLI-Plus2 gigs Corsair XMS PC6400 4 4 4 12 @810Dual OC'd XFX 8800GTX @ 2 gigs24 inch Widescreen LCD 16XAA/16XAFDual 19 inch LCD'sRaid-0+1PCPower and Cooling 1k Quad SLIhttp://home.comcast.net/~psolk/3monitorsa.htmlBackup RigAMD 4000 San Diego @ 2.72 Gigs Kingston Corsair XMS CL2XFX 7900 GTX Raid-0psolk.jpg

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Well, I'm hangin' on . . . but just. I've been following Dan for a while now and he generally has a pretty good grasp. In this article: http://www.dansdata.com/askdan00015.htmDan's discussion is about physical memory and why the OS only recognizes 3 gig, even with 4 gig installed. He goes on to describe that Vcards also map /reserve chunks of PhYsicaL memory. So it seems, this occurs in addition to the Vcard reserve of VirTuaL memory. Remember, in the following quote he is talking about PhysiCaL memory: "Power users with a hankerin' for dual graphics cards may be experiencing something of a sinking feeling, at this juncture. Yes, the 256Mb reserved for my little old graphics card means exactly what you think it means: Those two 768Mb graphics cards you can totally justify buying will eat one point five gigabytes of your 32-bit memory map all by themselves, cutting you down to a 2.5Gb ceiling before you even take the other reservations into account.This also explains why 1Gb graphics cards haven't hit the consumer market yet. Nobody yet needs anything like that much memory on one card for any desktop computer purpose, but some people would still be very happy to pay for such a card just for the pose value. It'd eat the whole of the fourth gigabyte of their system memory, though. And then they'd probably demand their money back.(This fact has apparently not stopped certain unscrupulous companies, coughDellcough, from allowing people to buy a computer with WinXP, 4Gb of RAM, and a pair of Nvidia's oddball 1Gb GeForce 7950 GX2 cards. Result: 56.25% of the installed memory absent without leave. You might as well have only bought 2Gb.)"It seems we have to be very careful to keep in mind there is Virtual (the FS discussion points) and separately, physical memory.The observation Dan seems to present is this: Systems with a standard 2 gigs of physical ram that are using SLI'd 8800GTs with 768Mb of memory each will leave the OS with only __ 2 gig (system ram) - (768Mb x 2, SLI'd 8800) = 464 Mbits __ of PhySicaL ram to work with.This is reminiscent of the old 640K to 1M Extended vs Expanded ram memory battle we use to fight. He forewarns the reader: "I apologise to any readers who have now remembered things that cause them to rock back and forth and mumble."Oh yea, I remember. I'm rocking away . . . as we speak!

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I'd just love to know why it's only certain machines that seem to have the issue. As Paul and others know, I've run exact test scenarios given to me by them including all the same addons etc, on a nearly identical machine and have never, not even once, seen the OOM error happen. I don't understand how it can be a system specific thing if it's a generalized flaw in the software.Regardless, if MS is taking responsibility for it, I'd venture there's really not much any of us addon makers can do about it. It's not just us, I know the problem occurs with other high end aircraft, Ultimate Terrain etc...

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Ryan,I fought this darn problem for six solid months and it only started after I combined all my addons and the presence of the Queen. We all know the Queen is a reletive RAM hog and UT had the shorline issues which were discovered later. Combined with a destination of a high fidelity addon airport was just asking for OOM trouble. The cure was basically two-fold; cut-out all background processes possible and also remove the shorelines from certain parts of UT.Now Vista, 768MB video, FSX, UTX, ASX (simconnect), and 744X? with decent sliders? Yea, I'll beleive it when I see it. I'm already encountering OOM with the LVL-D update and have just now opted to switch back to WinXP for comparison. I know plenty of add-on developers previously colaborated on the issue and we have all learned a lot from past experience. But the point is, the physical RAM limitation hasn't changed and more users are inching towards it daily.Don't just look at the number of OOM threads and the number of posts they contain, but the number of views most of those discussions received. I sure hope the 744X beta is being tested with a decent size video card, with UTX and ASX running along side it because I doubt very seriously that it uses any less RAM than its FS9 predesessor and the situation is bound to only get worse.regards,

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Well the number of page views doesn't really mean anything - I click on threads all over the place that aren't directly related to something I'm experiencing. This really is a minority of users we've had actually contact us about seeing OOM errors. I use a ton of addons myself like I said and I've never seen it even when doing exact step by step scenarios that produce it for others.

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