Memory Cards - IBM 7012 G Series Service Manual

Memory Cards

There are four types of memory cards as shown below. Memory cards can house from one
to four memory module kits composed of four memory modules each, which comply with the
JEDEC standard for 68 pin, ECC, 60 ns, 5 volt memory modules. The figure below illustrates
the types of memory cards.
MRE
Memory Card
Two Bank RLX
Memory Card
Four Bank NFX
Memory Card
SF5
Memory Card
See page 4-38 for the location of the memory cards on the system planar.
The figure below shows a standard memory module.
The maximum memory reachable with this kind of memory module is 1024MB, because up
to four memory module kits can be installed on the memory card.
Modules from different size kits cannot be mixed on the same memory card.
According to both the kind and the number of memory module kits installed on the memory
cards, these can be divided into the following configurations:
MM32, which gives 32MB memory contains four 8MB memory modules.
MM64, which gives 64MB memory contains four 16MB memory modules.
MM128, which gives 128MB memory contains four 32MB memory modules.
MM256, which gives 256MB memory contains four 64MB memory modules.
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Service Guide