Installing 14GB RAM Mac Pro Early 2008

[paulogic]

Hi there,

I've got a Mac Pro (2x2.8 Quad Core) Early 2008. The computer came with 2GB of RAM (2x1GB). Last year I bought an extra 4GB (2x2GB) from Crucial and installed them without any problem.

I just got 8GB (2x4GB) and I thought I was installing the chips properly, but OSX only shows that I have 10GB installed.

My configuration is as follows:

Riser A:

DIMM 1: 1GB
DIMM 2: 1GB
DIMM 3: 4GB
DIMM 4: 4GB

RISER B:

DIMM 1: 2GB
DIMM 2: 2GB
DIMM 3: EMPTY
DIMM 4: EMPTY

Anyone have any suggestions?

Thank you!

 

[Brisby]

Here's my suggestion -

Riser A

DIMM 1: 4GB
DIMM 2: 2GB
DIMM 3: 1GB
DIMM 4:

RISER B:

DIMM 1: 4GB
DIMM 2: 2GB
DIMM 3: 1GB
DIMM 4:

 

[Umbongo]

Here's my suggestion -

Riser A

DIMM 1: 4GB
DIMM 2: 2GB
DIMM 3: 1GB
DIMM 4:

RISER B:

DIMM 1: 4GB
DIMM 2: 2GB
DIMM 3: 1GB
DIMM 4:

You can't do that as they have to be installed in pairs.

The optimum configuration is A:4,4,0,0 B:2,2,1,1 as this places more equal amounts of memory on each riser.

 

[paulogic]

The optimum configuration is A:4,4,0,0 B:2,2,1,1 as this places more equal amounts of memory on each riser.

Thank you Umbongo! That worked like a charm! Much appreciated!

Cheers,
Paul