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ryan29121
03-11-08, 07:48 AM
Alright the computer I am building for someone has 2x2gb sticks of ram so 4gb total and is running xp and vista x64 dual boot. In Vista it has no problem running 4gb but in xp it only reads 2gb. Shouldn't xp read like 3.2 or 3.5gb? I know my computer at home reads 3.5. Any solutions for this. Thanks in advance.

Tr1cK
03-11-08, 07:51 AM
You might want to check a forum specific to your motherboard. I think there could be a BIOS option to allow you to see the other 1.2gb that XP is capable of, but I'm not sure.

andy_nv
03-11-08, 08:12 AM
There should be a remap memory option in the bios.

Dragunov
03-11-08, 09:15 AM
Alright the computer I am building for someone has 2x2gb sticks of ram so 4gb total and is running xp and vista x64 dual boot. In Vista it has no problem running 4gb but in xp it only reads 2gb. Shouldn't xp read like 3.2 or 3.5gb? I know my computer at home reads 3.5. Any solutions for this. Thanks in advance.

It depends on the other memory: VGA and such

Tr1cK
03-11-08, 09:38 AM
It depends on the other memory: VGA and such
Incorrect sir.

System RAM is only affected if you have an integrated video solution or if you have a Turbocache type of card that utilizes system RAM.

I believe andy_nv hit the nail on the head.

Dr.Nick
03-11-08, 10:43 AM
Incorrect sir.

System RAM is only affected if you have an integrated video solution or if you have a Turbocache type of card that utilizes system RAM.

I believe andy_nv hit the nail on the head.

Actually in a 32bit OS any device with ram will take up part of the 4GB address space. That includes, video cards, physx, and even our 64mb X-Fi's. You don't have to believe me but MS (http://support.microsoft.com/kb/929605/en-us) should be trustworthy enough.

For example, if you have a video card that has 256 MB of on board memory, that memory must be mapped within the first 4 GB of address space. If 4 GB of system memory is already installed, part of that address space must be reserved by the graphics memory mapping. Graphics memory mapping overwrites a part of the system memory. These conditions reduce the total amount of system memory that is available to the operating system.


As for the OP's question, there should be a memory remap/hole option on the bios that will at least allow XP-64 to use all the available memory

CapnKirk
03-11-08, 10:58 AM
You don't have to believe me but MS (http://support.microsoft.com/kb/929605/en-us) should be trustworthy enough.




:screwy: :D

Rakeesh
03-11-08, 11:57 AM
Incorrect sir.

System RAM is only affected if you have an integrated video solution or if you have a Turbocache type of card that utilizes system RAM.

Just to extend on what Dr.Nick already posted, its not the fact that the card uses up system ram, its the fact that the memory the card uses takes virtual address space in order for the kernel and drivers to interface with, regardless where the data is physically stored.

Tr1cK
03-11-08, 12:23 PM
Just to extend on what Dr.Nick already posted, its not the fact that the card uses up system ram, its the fact that the memory the card uses takes virtual address space in order for the kernel and drivers to interface with, regardless where the data is physically stored.
I stand corrected then.

XDanger
03-11-08, 03:38 PM
Just to extend on what Dr.Nick already posted, its not the fact that the card uses up system ram, its the fact that the memory the card uses takes virtual address space in order for the kernel and drivers to interface with, regardless where the data is physically stored.
Please to explain the Boot.ini switch now please.

ryan29121
03-11-08, 09:24 PM
If it was something in the BIOS wouldn't it be effected in vista as well? Vista reads all 4gb perfectly fine. I only get the problem in XP.

BronzeGod
03-11-08, 10:00 PM
The option is called Memory Remap in the BIOS, enable it and your problem will be fixed. Simple as that.

Dr.Nick
03-11-08, 10:02 PM
If it was something in the BIOS wouldn't it be effected in vista as well? Vista reads all 4gb perfectly fine. I only get the problem in XP.


If you've installed SP1 for Vista it will show all installed ram instead of available ram like it use to (still doesn't mean its usable though). Either way you should have more than 2GB of usable memory even in x86 XP. Check your bios for an easy fix.

einstein_314
03-11-08, 11:04 PM
If it was something in the BIOS wouldn't it be effected in vista as well? Vista reads all 4gb perfectly fine. I only get the problem in XP.
Not necessarily. For my Vista x64 install to see all 4Gb I need memory remap enabled. But in XP, it only sees 2GB. For XP to see 3.3GB, I need to turn off memory remapping. Weird I know. And a pain. But that's the way it is.

ryan29121
03-12-08, 08:19 AM
Thanks for the help. I will try this the next time I work on it.