Sorry if this has already been covered, but I couldn't find any discussion on this.Regarding the change to the boot.ini file, where, in XP/3GB /userva=XXXXis added to the end of the following line:multi(0)disk(0)rdisk(0)partition(1)WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetectFrom Phil Taylor's blog:"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 XXXX=2560, eg 2.5G, since that leaves 768m for the OS with a 786m graphics card. Much more reasonable."Now:3072-512 = 25603072-768 = 2304From Phil's discussion, wouldn't 2304 be a better choice for a 768M graphics card?For my 640MB 8800 GTS, I assume I should use a value of 2432?Is this concept as true for XP as it is for Vista?Thanks!Thomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180

Both XP and Vista 32-bit only have 4096 addresses. So if you assign 3072 to your 3GB of memory that only leaves 1024 addresses for your OS and Video card. Phil's saying the OS needs about 768 addresses.So if you have a 640 card then you need to leave 768+640 = 1408 for the OS and Video.So for RAM you can assign 4096-1408 = 2688RegardsJim

Hi guys, I remember reading something about this before as well.Would you be kind enough to expand on this for me.Where is the boot file.? [i can't remember]What are the benefits of this tweak.I have 3GB of ram in 2 x 1gb and 2 x 500MB sticks.Memstatus tells me I have 757MB of video memory.My card is an Ati RX800 TD256E Athlon 64 x 2 (dual core) overclocked by the allowable 10% making 2420.I have to say though that FSX runs very well for me, although it is not perfect. My main problem is that the aircraft initially appears in "grey" and the full colours appear after a couple of seconds.Many thanksRichard.

OK Thanks mate.Regards

Your boot.ini file is in the root directory of your boot drive, most likely C:. You'll also need to make an edit to the fsx.exe file (unless you've installed SP2).The main purpose of this tweak is to help people who are running out of memory (OOM errors), like when FSX shuts down and tells you it doesn't have enough memory to continue. In its default state, most programs do not allow you to access all the memory that is available (not physical memory, but operating system address space, which is usually much larger).It is not likely that this will help your grey aircraft problem, that is a speed of texture loading issue, tied to the speed of access/reading of files on your disk, memory speed, and your fsx.cfg.Other things you can do are:- use the task manager (ctrl-alt-del), go to the Processes tab, and get rid of unneeded processes.- Apply some of the fsx.cfg tweaks that adjust how FSX reads and stores textures.Regarding the 3G memory limit subject, It's probably best if you read what info is out there,Phil Taylor's blog is a good place to start:http://blogs.msdn.com/ptaylor/default.aspxSpecifically regarding this issue:http://blogs.msdn.com/ptaylor/archive/2007...ress-space.aspxand from there, he points you to:http://forums.avsim.net/dcboard.php?az=sho...ing_type=searchThomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180

Thomas many thanks for your reply.I did in fact find it and have had a "fiddle" only find [as you suggest] there was no advantage.I guess because I do not/ have not suffered from OOM.HOWEVER [i must be getting senile] I was sure that I had made a back up copy BEFORE fiddling but something has gone wrong.Would you be kind enough to post the boot.ini original so that I can revert mine back to normal.RegardsRichard

Everyone's boot.ini is different for a variety of reasons. But the only thing you should have done to yours was add those couple of switches in the OP.Thomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180