Max Usable Memory

[Mobius]

Well, I just got my 2 GB of memory, and ran memtest to check it all out.  When I tried to start it, it said, "Your version of Windows limits the amount of contiguous RAM a single program can allocate etc...".  Does this mean that having too much RAM is somewhat useless because it can't all (or more than a certain amount) be used to run a certain program (e.g. FSX)?  Is there a way to get around this, or am I just paranoid that I wasted $200?

Thanks again everyone.

[Sytse]

I think it's in the mobo...

My manual (ASUS P5B board) says I can only effectively run 3 GB of RAM under windows XP.

[Mobius]

So does mine, and the system registers that there's 2 GB there and everything, I was just wondering what the message means when it popped up when I started memtest (which ran to 300% with zero errors I'm happy to say ).

[NicksFXHouse]

I assume you only have 2 gigs installed and not 4. If so you may be getting a virtual memory error message.

Go to the system properties, advanced tab, performance button, advanced tab, change button...

post back how that is set for page file.

Typically, for 2 gigs of memory or higher that needs to be set to:

custom size: initial: 3070 max: 3070 on the WINDOWS boot drive

If not, set it that way, click SET, OK, APPLY and reboot

If you are running 4 gig it requires a special switch be added to the boot.ini file but even with that you will never get 4 gigs total to run in XPx32. XPx64 and VISTA will run 16 terabytes of memory

[Mobius]

I've got the max page file set to 3072 max (1536-3072).  Here's the message I get when I run memtest with "all unused RAM" as the amount to test, so when I run two seperate memtest sessions simultaneously with the smaller sizes, it works just like it should.  



All I was wondering is if there is some limit set by Windows on the max amount of RAM allocated to programs other than memtest (like FSX, FS9, etc...)?

Thanks for the responses so far.

[NicksFXHouse]

Alright... I understand now,

what you aare seeing is a message that is designed into the test program.

No, windows does not limit memory to software. The software is programmed to allocate a block of memory on program boot. For FS9 it 768mb if its available, for FSX its 1gig if its available however if more is available it will use more.

WindowsXP x32 has a limit on the maount of memory it will use. XP x64 does not. If you to run that memtest program in xp x64 you would not se tha message.

[Mobius]

So would there be any performance gain swithing from 32 to 64 bit?

[NicksFXHouse]

So would there be any performance gain swithing from 32 to 64 bit?

frames, no

smooth, yes

reason, bandwidth available to the system from the OS.

and that is assuming your motherboard and all devices have good x64 driver support.

Its not a miracle change however I find overall FS9 runs much smoother in x64


if you are expecting a huge leap in performance, that not going to happen