ECC registred memory

[rs232]

Hi, I've just bought a second hand tyan (S2915) motherboard with 3x1GB of Patriot memory DDR2-667 ECC Registered. As this is a dual CPU I need to have "balanced" memory.
Now, I was looking to buy an additional Gb do run at 4Gb in total.
Now, that memory new is incredibly expensive (£130($250)/Gb)!
So I was looking for a cheaper alternative.
I've found this on ebay:

Samsung 1GB PC2-5300P DDR2-667 ECC Registered Memory which has got a more than reasonable price.

Now' I've got 3 questions for you guys:
1) What is the "P" at the end of the name?
PC2-5300P

2)
The seller mentions something I don't quite understand:
"These chips only work in pairs so please know what you're buying"
Does this means, that the pair needs to be of the same brand?
Or that to operate needs to be a pair like 2x512Mb / 2x1Gb and not
individually 1x1Gb ???

3) Would you advise to mix 2 different memory vendor considering that old and new memory (on paper) have exactly the same specs (ECC buffered)?


Thanks a lot for your help!
rs232

 

[RichardB]

Go to the "Crucial" memory website.

 

[Big B]

While you probably can mix the brands, you're less apt to run into trouble by buying the same sticks. Server motherboards can be picky about which sticks you run in them, so unless you can exchange the stick or get a refund for it, it'd be better to pay a little more for the Patriot than give yourself some trouble by trying to run different sticks on the board.