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Old March 11th 04, 02:12 PM
CBFalconer
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Mark M wrote:
CBFalconer wrote:

Nothing uses parity checking today - that requires writing
individual 9 bit bytes. Expanded to a 64 bit wide word (for
the various Pentia etc.) the parity or ECC bits both fit in an
extra 8 bits, i.e. a 72 bit wide word. If todays systems have
no ECC they have no checking of any form. ECC is actually no
harder to handle on wide words.

Memory configurations that can use parity can use ECC, the
reverse is not true.

Exception - some embedded systems with smaller memory paths
may use parity.


Does the motherboard have to support ECC?


Yes


Or can you always put a stick of ECC memeory where there had been
non-ECC memory before?


No. Even if the MB supports ECC you have to have ALL the memory
ECC capable before it will function. Otherwise the system can't
tell a massive failure from a non-ECC area.

--
Chuck F ) )
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