Question Maximum DIMM DDR2 RAM supported ?

[kbidols]

Hi, I have an old PC with a Gigabyte Technology Co. Ltd. G31M-S2C (Socket 775) motherboard. While browsing through their website, I found out that the maximum RAM supported is 4GB. The motherboard has 2 slots, which at the moment are filled with 2x2GB DDR2 stick.

This is the information provided on their website HERE:

1. 2 x 1.8V DDR2 DIMM sockets supporting up to 4 GB of system memory
2. Dual channel memory architecture
3. Support for DDR2 1066(O.C.)/800/667 MHz memory modules
   (Go to GIGABYTE's website for the latest memory support list.)

Now, what I am curious is how much memory can I actually install? Is it possible to install 2x4GB RAM (a total of 8GB) or does it only support 4GB RAM in total for the 2 slots available?

Please do help explain. Thank you in advance.

 

[kerberos_20]

it only supports 4GB ram

 

[BFG-9000]

It's even worse than that, because the G31 chipset does not support memory remapping so APIC or PCIe memory space must take addresses from physical memory locations if 4GB (the maximum supported DRAM address decode space) is installed, so there will be physical memory that exists yet is non-addressable and therefore unusable by the system. How much is lost depends on what PCIe devices are installed.

What this means is even with the 4GB you currently have installed, ~0.75GB should show up as "Hardware Reserved" in Windows' resource monitor and unusable whether or not you are using the IGP and even if you are using a 64-bit OS. So 3.25GB is generally the maximum usable memory in both 32-bit or 64-bit Windows 10 on G31. I don't know how it behaves in Linux or Hackintosh.

Note there are certain programs that can access memory above 4GB with this chipset. Back in Windows XP days I used Gavotte Ramdisk and put the swapfile up there to use the otherwise inaccessible RAM. When this didn't work in Windows 7, I used it for eBoostr disk cache (essentially like ReadyBoost on a ramdisk). So yes, you can install more and it should be recognized by the BIOS... but it doesn't work normally as memory, at least not in Windows. Though it may still be usable for something.

 

[kbidols]

it only supports 4GB ram

Thank you.

 

[kbidols]

It's even worse than that, because the G31 chipset does not support memory remapping so APIC or PCIe memory space must take addresses from physical memory locations if 4GB (the maximum supported DRAM address decode space) is installed, so there will be physical memory that exists yet is non-addressable and therefore unusable by the system. How much is lost depends on what PCIe devices are installed.

What this means is even with the 4GB you currently have installed, ~0.75GB should show up as "Hardware Reserved" in Windows' resource monitor and unusable whether or not you are using the IGP and even if you are using a 64-bit OS. So 3.25GB is generally the maximum usable memory in both 32-bit or 64-bit Windows 10 on G31. I don't know how it behaves in Linux or Hackintosh.

Note there are certain programs that can access memory above 4GB with this chipset. Back in Windows XP days I used Gavotte Ramdisk and put the swapfile up there to use the otherwise inaccessible RAM. When this didn't work in Windows 7, I used it for eBoostr disk cache (essentially like ReadyBoost on a ramdisk). So yes, you can install more and it should be recognized by the BIOS... but it doesn't work normally as memory, at least not in Windows. Though it may still be usable for something.

Thank you. This is very clear.