>On Dec 2, 11:43am, "Michael Graff" wrote:

>} My thought on memory parity is that it is a holdover from the dark
>} ages of computing and isn't really needed anymore.  I would be

>     I totally disagree.  Anything that increases reliability is good,
>conversely anything that decreases reliability is bad; therefore,
>dropping memory parity is bad.  Not knowing when your memory is
>corrupt is a very very bad thing [tm].  This only occurs in the Mac
>and PC markets.  The upper markets, workstation, mainframe,
>supercomputer, etc. would never stand for this kind of nonsense.

I disagree with your disagreement.  To a point.

How many parity errors has the average person seen?  I would suspect
the average is less than one.

Modern memory is pretty darn reliable.  I run my motherboard with
parity turned off because it actually causes me problems when I have
write-back caching enabled at the same time as my BusLogic
bus-mastering SCSI controller is going all-out.  With parity disabled,
I get uptimes of multiple months.  It also allows me to throw in less
expensive, yet fast, memory.

The reason Intel stopped making parity systems is not to pull the wool
over consumers' eyes, but because memory just doesn't fail very often
any more in consumer systems.  The emphasis is on consumer systems.
I'm talking about my home machine, here.

Now, if you're talking about a mission-critical server, then yes,
error detection should be a requirement.  But, I'd say in that
situation, a single-bit parity check isn't really enough.  If you're
going to be running in that crowd, you should demand no less than full
ECC memory correction.

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  Michael L. VanLoon                                 michaelv@HeadCandy.com
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