Ram not registering - have 4x1gb windows only addressing 3gb

[dubplatepressure]

Running XP pro SP2
P5ND2 SLI mobo
2 sets of corsair pc5300 2x1GB ram, total 4gb
805 D chip
X1950xt
250 SATA hd
680w psu



Bios registers 4 gb installed memory but windows is not addressing the final 1 GB. I read something I didnt totally understand about PAE and that 32 bit XP cannot address more than 3 GB... not sure if that's true or not...

Any help?

8O

 

[Hatman]

Yeo it is im afriad.


A 32bit operating system can only use something like 3.27gb of memory. But as 4x 1gb sticks, can use 3gb.

 

[croc]

(sigh) One more time, boys and girls. Get out your calculator and calc 32 to the 2nd... Comes out as 4 GB, eh?

What happens to the other GB? (sometimes less, sometimes more...)

Go look it up. Start with Google, or take a shortcut and try msdn... (I'll give a bit of a hint... Has something to do with drivers, other system overheads, etc...)

 

[dubplatepressure]

thanks hatman, I actually did google search it, but I guess I'm not as technically savvy as someone like Croc, so I apologize for making him or you feel reduntant...

Cheers

 

[Dahak]

Don't worry as this is quite normal.A 32bit OS can only utilize something like 3.2gigs of memory.You want to use anymore,you need to go with a 64 bit OS.Goodluck.

Dahak

AMD X2 5600+ @ 2.8ghz(stock)
M2N32-SLI DELUXE MB
2 GIGS DDR2 800 RAM
THERMALTAKE 850WATT PSU
7950 GX2 560/1450
ACER 22IN. LCD
SMILIDON RAIDMAX GAMING CASE
80GIG/250gig SATA2 HD's
XP MCE
3DMARK05 14644

 

[notherdude]

I see you were wondering about PAE. IIRC, PAE is sometimes used to get 32 bit SERVER operating systems to use that missing RAM for SOME applications, such as SQL server. It is a complicated explanation I have never fully understood but it seems there is no way for us everyday 32 bit users to do it.

A 32 bit OS can only ADDRESS 4 gig of RAM. Some of that 4 gig limit is reserved for other things such as your video card RAM for example. Hence you end up with 3.2, 3.0 or 3.5 etc. of useable RAM



To use all 4 gig you need a 64 bit OS, (and the correct CPU and chipset.)

 

[dubplatepressure]

I dont quite understand why my OS would reserve a full gig of ram for other things when it doesnt when I only have 2 gb installed... or why it would allocate memory for shared ram on my GPU when my gpu doesn't use shared memory.... but oh well.

I dont fully understand the reason, but at this point it doesn't matter.

Thanks for the help guys, I guess I'll move to a 64 bit OS.

 

[jitpublisher]

Are you having problems with it the way it is?
Do you actually need the 4 gig of memory? By far most people don't need or will notice any difference between 2 and 4 gig.
64 bit OS's (Windows) can be troublesome with driver/hardware availability/compatabilty.

 

[dubplatepressure]

I'm just looking for better frame rate on games like Colin Mcrae DIRT, Stalker, etc.

 

[nukemaster]

its a known windows limitation.

You should still have plenty left over to game.

 

[jitpublisher]

Look elsewhere to improve your frame rates. Nukemaster is right, looking for more memory won't help you here.

 

[jt001]

You probably won't notice the lost memory, still, it would bug me to know it was there and wasn't being utilized.

As other people have said, you need a 64-bit os to utilize it all, I use xp64 and I haven't had any issues so I'd recommend giving it a try, you can also download a 6 month trial from ms, to make sure everything works with it before you spend any cash.

 

[TheRodent]

I dont quite understand why my OS would reserve a full gig of ram for other things when it doesnt when I only have 2 gb installed... or why it would allocate memory for shared ram on my GPU when my gpu doesn't use shared memory.... but oh well.

I dont fully understand the reason, but at this point it doesn't matter.

Thanks for the help guys, I guess I'll move to a 64 bit OS.

Your system does reserve 1gb for other uses even when you only have 2gb of ram installed. The reason it does not impact the visible memory is that this is 1gb of the virtual memory address space. That still leaves 3gb available to map to the 2gb of physical memory.

Your GPU may not use shared memory but depending on operating systems it may be memory mapped into the virtual address space.

 

[Mondoman]

To clarify, there are only 4GB of available memory *addresses*. The issue is a shortage of addresses to assign to the physical RAM (since in order to use the physical RAM, it needs an address). When you only have 2GB of physical RAM installed, there's no problem because the system has 4GB of addresses to work with, so even after using up something like 1GB of addresses for the hardware and setup, more than enough addresses are left over for all your 2GB of physical RAM.