Memory naming conventions

[midway]

I have to deal with ram pretty regularly at work. I've gotten used to reading what type of memory it is just by speed markings that seem to be on most ram, an example being PC2-5300R-555

I know that the letter after the speed can stand for various things, the ones I know are

E - ECC
R - ECC Reg
F - Fully buffered
U - Non-ECC

but what does this one stand for

P - ???

Anyone have any ideas?

 

[g8wayrebel]

Parity??

 

[midway]

Nah, it's not that. The only thing I've seen it on has been IBM memory with ChipKill.

 

[RebateMonger]

HP references it in their ML150 Server line

Every reference I find designates lists "P" as ECC Registered memory, the same as "R". Could just be a difference in naming convention among manufacturers.

 

[tcsenter]

Originally posted by: midway
Nah, it's not that. The only thing I've seen it on has been IBM memory with ChipKill.

Which requires address and command parity to support the complete ChipKill feature set, in addition to data parity. P = Registered DIMM with address/command parity

 

[midway]

Ah, wonderful, thanks for the info. I wasn't 100% sure what chipkill actually did.