XP Pro Sp2 RAM Limit?

[[GSV]Trig]

I've just stuck another 2Gb in a machine at work giving it 4Gb in total, the BIOS says its got 4gb, CPUID says its got 4Gb but System Properties says 2.75Gb....

[ExceededGoku]

3GB is maximum system will see, but thats nota problem tbh. It will still work as roughly 4GB . If you're not impressed try Windows x64. (I recommend dual boot)

[Moby-Dick]

http://www.microsoft.com/whdc/system...AE/PAEmem.mspx

[[GSV]Trig]

The machine is an X64 box, x2 3800 so surely it should see it, or when you say machine do you mean OS or the hardware?
x64 is a option as we have VLK for x64 use

[FatalSaviour]

Both the OS and the hardware Trig.

[mark19632]

ExceededGoku is refering to using Windows X64 OS rather than the CPU being 64 Bit

[[GSV]Trig]

ExceededGoku is refering to using Windows X64 OS rather than the CPU being 64 Bit

I know, hence me saying I can stick XPx64 on it...

[[GSV]Trig]

Hmmm, done the /3gb thing and its still showing 2.75gb on system properties...

[ExceededGoku]

hmm.... thats rli weird.
in the bios there is an option to put S/W and H/W over 4GB or something like that in the memory settings, try enabling those.

[[GSV]Trig]

I've checked the Memory Hole thing in the BIOS and that then shows in the BIOS as ~2Gb so I'm guessing thats not it...
It was set to auto and I've now left it auto, I might just give it nuts for now, as long as the machine works, could then install XPx64 on it or wait for Vista as were on SA so should get VLK's for it..

[directhex]

could be many things. x64 is the most simple solution, though

[[GSV]Trig]

Yes it is but as XPx64 seems to be a stop gap until Vista comes out I cant see me getting the driver support I need for the machine...

[Agent]

I've just stuck another 2Gb in a machine at work giving it 4Gb in total, the BIOS says its got 4gb, CPUID says its got 4Gb but System Properties says 2.75Gb....

It has 4GiB, but can only address 2.75GiB (in your system).
Unless you have a server based board, or at least a very high-end one that is designed to fully address 4GiB - you cant.
Note when you look at motherboard specs, "supports up to 4GiB" is NOT the same as "Addresses up to 4GiB".
A normal motherboard has ~4GiB of addressable space. Almost everything that is used in the system has to be given some of this space, which obviously eats into it. Critical components come first, but normal RAM is pretty far down on the list.
By the time your system gets to addressing the RAM is own space, it'll basically just give it whats left.
This has no link with the OS at all.

http://support.asus.com/faq/faq.aspx...s&model=P5P800
That has a list of chipsets which have the "memory swap" function allowing you to overcome the limit. Click on the "4GB memory installed but less memory size detected" link.

Hope that helps

[Paul Adams]

Here are a couple of threads discussing this issue, and a Microsoft KB article describing it and why it happens:

Why does 32-bit Windows 2003 R2 see all 4GB of my RAM?

4gb of Memory Not Detected in Windows Fix and SP2 3gb Limitation

The amount of RAM reported by the System Properties dialog box and the System Information tool is less than you expect after you install Windows XP Service Pack 2 (KB888137)

I deal with servers much more than workstation versions of Windows, and even then I tend to use 64-bit Windows - but we do occasionally have issues with some server-class hardware that doesn't see 100% of the installed RAM due to BIOS limitations or designs (typically commnication with onboard hardware uses up some of the higher-end address space).

The /3GB switch does not affect the memory visible by Windows at all, and has nothing to do with physical memory installed - all it does it to move the split of user mode & kernel mode memory within the 4GB (32-bit) range from 2+2 to 1+3 - and even then the applications have to be compiled with /LARGEADDRESSAWARE to be able to address up to 3GB of user mode memory.

Most 32-bit apps will be unable to address more than 2GB of memory even if there is way more than that installed, add on the chunk that the kernel would use (let's be extreme and say 1GB) and you've got a hefty chunk of physical memory going unused.

[TheAnimus]

as Paul said this is simply a case of people not expecting that much RAM to be maid available.

If your running much in .net, then the performance boost will be there for you in 64bit win, if your running multiple applications, then the performance boost in 64bit will be there (as i belive WoW... the emulation of 32bit will allow each app to use seperate memory as long as its a seperate instance of WoW, not sure about this thou, not got a nice enough box to test it on!)

Do you actually NEED that much ram thou?

[[GSV]Trig]

Its our design machinem, has several InDesign, Photoshop, Illustrator and random other stuff all open at the same time...