What MB can support "usable" 4GB DDR2?

[hankjones]

I'm been searching and searching for a MB that can use all 4GB DDR2 memory, but it seems like most MB that say they support 4GB actually have a note in the manual that usually says something like "due to chipset resource allocation, the system may detect less then 4gb of system memory when using 4 1GB memory sticks". Is anyone getting 4GB usable in the OS with their motherboard?

I'm looking for something that supports Intel 775 socket, has sata raid 0 at least, and uses 667DDR2 memory

 

[Harvey]

I found three boards that look like they meet your requirements:

Abit AL8

Abit AL8-3rd Eye II

AOpen i945Ga-PHS

No guarantee that they're actually available or that they work as spec'd. Good luck. 🙂

 

[hankjones]

Thanks for your reply, i tried looking up the manuals, here's what I found

AL8: "Due to chipset resource allocation, the system may detect less than 4GB of system memory in the installation of four 1GB DDR2 memory modules."

AL8-3rd Eye II: couldn't download the manual.

AOpen i945Ga-PHS: didn't indicate any limitations!

Do you know what limits the addressable memory? I?ve seen some diagrams, and it looks like memory is attached or associated with the south bridge. And the AL8 is 945P, AL8-3rd Eye II is 945P, and Aopen is 945G?

 

[hankjones]

I mean North Bridge chip set

 

[Peter]

Unless you're going with a server grade chipset that can relocate the overlap to above the 4-GByte border AND a processor that is able to reach it (i.e. a Xeon on the Intel side, or any AMD64 setup) AND an operating system that actually uses this capability, you're not going to get it.

Reason: 32-bit address space is 4 GBytes total. You can't plaster it all with RAM, you need to leave room for system essentials, your graphics card's frame buffer memory, other PCI peripherals and many more misc bits and pieces. Hence, no 4-GB RAM size there.

 

[hankjones]

What about this combo?

Intel Pentium 4 650, EM64T

P5ND2-SLI Deluxe (North Bridge is Nvidia nForce 4 SLI Intel Edition, it specifies 8GB DDR2 support for 64 bit OS platform only)

Windows 2003 64bit


In the manual it says "Due to chipset resource allocation, the system may detect less than 8GB system memory when you install for 2 GB DDR2 memory modules", but it doesn't say anything about 4 1GB DDR2 memory modules.

 

[hankjones]

For those who are looking for the same thing. Here is a configuration for 4gb on Windows 2003:

Asus Motherboard: P5ND2-SLI Deluxe
PQI Memory: PQI25400-1GDB (4 1gb sticks)
Graphics card: Nvidia PCI (not PCIE card)

The Motherboard recognizes 4GB, and in order to get Windows 2003 standard or enterprise to use it, you will have to put /pae option under the boot.ini. Just as a FYI, the memory is only running at 4.4.4.12 533MHZ.

I've manually configure the timing, and set the voltage to 2V, but still reconized at 533. I may troubleshoot that later...

 

[Peter]

hank, the chipset cannot address memory past the 8-GByte border. Hence, if you install four, you'll get 3.something contiguous and the rest relocated to above 4 GByte. However if you install 8, the entire space for RAM is filled, no relocation possible.

 

[lifeguard1999]

Originally posted by: Peter
Unless you're going with a server grade chipset that can relocate the overlap to above the 4-GByte border AND a processor that is able to reach it (i.e. a Xeon on the Intel side, or any AMD64 setup) AND an operating system that actually uses this capability, you're not going to get it.

Reason: 32-bit address space is 4 GBytes total. You can't plaster it all with RAM, you need to leave room for system essentials, your graphics card's frame buffer memory, other PCI peripherals and many more misc bits and pieces. Hence, no 4-GB RAM size there.

Thanks for the info. I never knew that.