biosmemorymotherboard
I have a 945GCM S2L Motherboard which has 4GB memory (2x2GB) running windows vista x64.
The RAM is getting reported as 3GB in the BIOS, Total Physical Memory also shows 3GB, Task manager also shows 3GB. Am I missing anything ?
EDIT: Is there any way of updating BIOS from a x64 Vista installation, 16bit applications are not supported by x64 & my manufacturer does not have a 64 bit install
From your motherboard specifications page:
*When installing total memory of 4GB capacity or more, Windows 32-bit operation system may only recognize less than 3GB. Hence, a total installed memory of less than 3GB is recommended.
This is due, as you have found, to your graphics card and other devices needing to be mapped into the 32-bit (4GiB) address space.
Generally this is only seen with a 32-bit operating system, but if the motherboard is particularly old and badly designed then it can happen with a 64-bit operating system as well.
See my answer to What limits a motherboard from supporting more memory?, as well as other questions such as Why does my sytem only uses 3.2GB of my 4GM RAM?
Basically the first thing to try is running a 64-bit OS, for example a Linux LiveCD such as Ubuntu, to see if that can see the full 4GiB. If it cannot then it is a motherboard issue. If the memory can be seen then you will need to reinstall your current Windows version with a 64-bit version to use the whole 4GiB.
Make sure the Memory Remapping BIOS setting in the Advanced tab is enabled:
Best Answer
Your motherboard does support 4gb of memory, with some caveats. Your onboard video will reserve some of that memory you have on there for its use, and you will also have some of the memory being used for system maintenance and such. After all this is said and done, you will only have 3 gb available for the os and any apps to use. This is the bad part about onboard video... shared memory allocation.