4gb displaying as 3gb in XP - is this normal?

Toggle sidebar Toggle sidebar
D

dannyaa

Distinguished
Jan 1, 2001
594
0
18,980
I just upgraded from 2gb of RAM to 4gb. In Windows XP under "My Computer" it shows that I have 3gb of RAM. However, I havw 4gb. I used CPU-z to check this, and cpuz says I have 4096mb and shows RAM in all 4 slots.

Why is XP saying it only sees 3gb? Is this normal? (I have XP pro with sp2 and all latest patches).
 
J

jordanaustin

Distinguished
Apr 5, 2006
7
0
18,510
your post says you just upgraded from 2 to 3. Then XP would be right.

But assuming you upgraded from 2 to 4, I've never heard of xp being off an entire gig.
 
D

dannyaa

Distinguished
Jan 1, 2001
594
0
18,980
Sorry, fixed post to read that I upgraded from 2gb to 4gb.

So XP can't see more than 3gb unless it's the 64-bit version? I thought it was that xp supported up to 4gb, and then you need 64-bit to see more?

Also, oddly, Adobe After Effects 7.0 when I boot it reports that I am using 2% of 2gb of RAM...?? So now I have 3 different readings:

Cpu-Z: 4gb
WinXP: 3gb
AE7.0: 2gb
 
F

Frodaddy6

Distinguished
Jan 19, 2007
13
0
18,510
If you use Windows XP or Vista 32-bit, 4 gigs will show up as less. There's limitations to the 32-bit architecture and that's one of them. I have 4 gigs installed myself, and only 3.05 gigs show. The chipset on my mobo will use the last gig for device memory addresses, in which I am glad because I've heard of some XP machines with 4 gigs having a lot of problems. Read these four articles from Microsoft:
http://support.microsoft.com/kb/279151
http://support.microsoft.com/kb/929605
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx
http://support.microsoft.com/kb/108393/.
 
gm0n3y

gm0n3y

Distinguished
Mar 13, 2006
3,441
0
20,780
The issue here is that for a 32-bit operating system, ram addresses can only be 32 bits long and that equates to only 3 or so GB of ram. Its a little more complicated than that, but that's the gist of it. No amount of patching will fix this, you'll have to use a 64-bit OS.
 
D

dannyaa

Distinguished
Jan 1, 2001
594
0
18,980
How do I know if my mobo will use that RAM? I've got an ASUS A8N-SLI Premium...

So I upgraded to 4gb for Vista 32-bit which I'll be getting soon... was that a waste to get 4gb? If my mobo doesn't use that RAM, is it just not used, or does it just not show up?

Also, what are the main issues XP may have with 4gb? Would I be best to take one stick out?
 
gm0n3y

gm0n3y

Distinguished
Mar 13, 2006
3,441
0
20,780
Get the 64bit version of Vista, you have a 64bit processor so you will be fine. No reason to get old tech if you don't need to. It has nothing to do with your motherboard (as far as I know). Like I said before, the OS (windows) you have is 32bit and will NEVER recognize more than 3GB or so. It isn't that XP has issues with it, its that its a 32bit OS and can only address RAM with addresses no longer than 32 bits, so it can't handle any more than that.
 
gm0n3y

gm0n3y

Distinguished
Mar 13, 2006
3,441
0
20,780
I have heard mixed opinions about the 64 bit driver support. I'm sure that they will be nonexistent in another year. Then you will start having issues with 32 bit drivers. Vista was originally supposed to be 64 bit only, but MS caved once they realize that nobody with a 32 bit P4 could run their OS, so they made a 32 bit version (which is stupid, since you wouldn't want to run it on any 32 bit processor).
 
Mondoman

Mondoman

Splendid
Jun 22, 2006
5,678
1
25,810
...
So I upgraded to 4gb for Vista 32-bit which I'll be getting soon... was that a waste to get 4gb?
Click to expand...
Yes.
...If my mobo doesn't use that RAM, is it just not used, or does it just not show up?
Click to expand...
Since it can't even be "seen", it can't be used.

...Also, what are the main issues XP may have with 4gb?
Click to expand...
None - it just won't see all 4GB
...Would I be best to take one stick out?
Click to expand...
Doing that will leave at least part of your RAM to run in single-channel mode. Best bet would be to take out 2x1GB and sell them, replacing them with 2x512MB which will give you 3GB total.
 
gm0n3y

gm0n3y

Distinguished
Mar 13, 2006
3,441
0
20,780
... Vista was originally supposed to be 64 bit only, but MS caved once they realize that nobody with a 32 bit P4 could run their OS, ...
Click to expand...
Pretty much all the P4s sold for at least a couple of years have been 64-bit capable.

Which is why I said a 32 bit one, some of the newer 64 bit ones could run Vista (albeit not well), but I doubt any older P4 (32 bit) could. And AFAIK, those were the last 32 bit processors made (by Intel and AMD anyways). If MS just made Vista 64 bit only, then we wouldn't be having these driver issues, since hardware companies wouldn't have to support both standards.
 
S

scubageek

Distinguished
Mar 8, 2006
101
0
18,680
64 bit Vista isn't that bad.

Actually out of the box, it has just been as stable for me, as XP with latest SP.

Annoying little things that can be turned off, make Vista much better. I don't need to be asked if I am sure I want to run some program, I wouldn't have started it if I didn't want to run it.

As for driver support, it is there, and a lot of 32bit drivers do work with Vista or let me say, the ones I needed did work. I also know 64bit XP drivers also work with Vista.

If I was in your shoes, I would keep my 4gig of RAM and just upgrade to 64bit Vista. Easiest solution you have.
 
K

kamel5547

Distinguished
Jan 4, 2006
585
0
18,990
Sorry, fixed post to read that I upgraded from 2gb to 4gb.

So XP can't see more than 3gb unless it's the 64-bit version? I thought it was that xp supported up to 4gb, and then you need 64-bit to see more?

Also, oddly, Adobe After Effects 7.0 when I boot it reports that I am using 2% of 2gb of RAM...?? So now I have 3 different readings:

Cpu-Z: 4gb
WinXP: 3gb
AE7.0: 2gb
Click to expand...

XP can see 4GB of addressable space, your RAM is one component that takes up addressable space.

The following components require memory address space:

System ROM
APIC(s)
Integrated PCI devices, such as network connectors and SCSI controllers
PCI cards
Graphics card
PCI Express cards (if applicable)
Click to expand...

Thus your total memory mileage will vary based on your particular system.

Get the 32 bit vista and mail in for the 64 bit (or if you can find the 64 get a 64 bit version, I believe only Ultimate comes in with 64 discs by default).
 
A

aztech

Distinguished
Apr 13, 2004
114
0
18,680
For all those people saying a 32bit os can not access 4gb of ram I say DO THE MATH

a 32-bit processor uses 32 bits to refer to the location of each byte of memory. 2^32 = 4.2 billion, which means a memory address that's 32 bits long can only refer to 4.2 billion unique locations (i.e. 4 GB).
 
306maxi

306maxi

Distinguished
Feb 7, 2006
679
0
18,980
... Vista was originally supposed to be 64 bit only, but MS caved once they realize that nobody with a 32 bit P4 could run their OS, ...
Click to expand...
Pretty much all the P4s sold for at least a couple of years have been 64-bit capable.

Which is why I said a 32 bit one, some of the newer 64 bit ones could run Vista (albeit not well), but I doubt any older P4 (32 bit) could. And AFAIK, those were the last 32 bit processors made (by Intel and AMD anyways). If MS just made Vista 64 bit only, then we wouldn't be having these driver issues, since hardware companies wouldn't have to support both standards.

Wrong! Vista runs just fine on my 2.8Ghz Northwood and that's not a "new" P4. Vista is nowhere near as bad on power as everyone seems to state.

The issue here is that for a 32-bit operating system, ram addresses can only be 32 bits long and that equates to only 3 or so GB of ram. Its a little more complicated than that, but that's the gist of it. No amount of patching will fix this, you'll have to use a 64-bit OS.
Click to expand...

32bit OS's can address 4Gb of memory BUT things like graphics cards also have memory and there are other bits of memory dotted around your mobo. To the OP disable anything like network ports that you don't need as every device on your board will use up memory addresses and if you do this it should make more of your RAM usable.

Tbh most people tend to end up with 3.5Gb of RAM so I think you're a bit unlucky here. Perhaps put in a graphics card with less memory and you will "gain" a bit more memory as well :)
 
J

jonkc

Distinguished
Apr 14, 2006
99
0
18,630
For all those of you saying that XP cannot see or use more than 3gb, check your facts. A quick search on MS site states
Windows XP Professional and Windows Server 2003 Memory Support. The maximum amount of memory that can be supported on Windows XP Professional and Windows Server 2003 is also 4 GB. However, Windows Server 2003, Enterprise Edition supports 32 GB of physical RAM and Windows Server 2003, Datacenter Edition supports 64 GB of physical RAM using the PAE feature.
Click to expand...
The article can be found here: Memory Support and Windows Operating Systems

It does state that
The virtual address space of processes and applications is still limited to 2 GB unless the /3GB switch is used in the Boot.ini file.
Click to expand...

JonC
 
T

tgstyle

Distinguished
Apr 28, 2006
58
0
18,630
Check this link http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx

Note it says not all devices may support this.

Edit *
"Although support for PAE memory is typically associated with support for more than 4 GB of RAM, PAE can be enabled on Windows XP SP2, Windows Server 2003, and later 32-bit versions of Windows to support hardware enforced Data Execution Prevention (DEP)."

"Operating System Support. The PAE kernel is not enabled by default for systems that can support more than 4 GB of RAM."
 
You must log in or register to reply here.

TRENDING THREADS

Latest posts

Moderators online

Share this page

COMPANY
RESOURCES
FOLLOW
Top Bottom