[vox-tech] ECC memory --- is it worth it? (semi-OT)

[Bill Broadley]

hajhouse wrote:
> På 2007-04-10, skrev Rick Moen:
>> Quoting hajhouse (hajhouse at houseag.com):
>>
>>> I've never understood the distinction. What's different between
>>> registered and unregistered DIMMs?
>> Registered RAM has a buffer through which data are checked in and out of
>> the stick's address space, to help ensure data integrity.  It's
>> generally supported only on server boards.  Unregistered RAM is more
>> often referred to as "unbuffered".  See:
>>
>> http://www.mushkin.com/doc/techSupport/papers/registered.asp
> 
> I see. So then, for the strongest assurance of data integrity, one would
> choose registered ECC RAM.

Er, sort of.  Sure if most paranoid it adds something.  But the additional
buffer adds cost, complexity, and damages performance.  It's worth it
on servers mostly to allow for larger dimm counts.

For instance with non registered memory you often can have 4 low density
dimms, 2 high density dimms, or downclock the memory bus for 4 high
density dimms.  Registered memory allows for 8 high density dimms
at full clock rate.

So mainly it's a mechanism to allow for more dimms more than improving
reliability with a lower number of dimms.