Q: Any idea why http://support.apple.com/kb/HT4433#3 and Memory Slot Utility differ?
Hi,
According to Apple, at http://support.apple.com/kb/HT4433#3 , adding memory to a Mac Pro (early 2009, eight core (two quad-core))
is done by pairing the SIMMs (e.g., slots 1&2, or 3&4).
But...
when I install 4, 4, 2, 2 in one module, and 2, 2, 2, 2 in the other, the system boots ok and the Memory Slot Utility pops up saying it should be 4, 2, 2, 2 and 4, 2, 2, 2 (which I'd expect, based on mainframes I've worked on elsewhere!).
If I change the memory to match the MSU, everyone's happy (except the manual writers).
Any idea why the manual doesn't require balanced loading? (E.g., was this a quirk of the 2009 Mac Pro and earlier/later ones require the "pair them up" approach (and the manual wasn't updated)?
Or?
Just wondering (question arose when I tried to install two 8 GB DIMMs ... giving up for now, suspect they didn't play well with existing DIMMs)
thanks,
Stan
Mac Pro, Mac OS X (10.6.8), Adding memory, memory slot utility
Posted on Feb 28, 2013 4:30 PM
Mac Pro (early 2009
You are referring to the wrong section of the manual. The section of the manual requiring pairs is for a Mac Pro with removable daughter-cards -- the previous generation of Mac Pro (2008 and previous) which uses paired DIMMs in adjacent slots.
Your Mac Pro features slots 1,2,3 as free and independent slots, while slot 4 is shared with slot 3. (and same on the other side)
The correct diagrams are there, but you have to dig carefully to find them. Look for the tag:
In an 8-Core Mac Pro (Early 2009)
then be very careful not to scroll down too far, or you end up inside the guts of the 2008 model with the removable cards.
Posted on Feb 28, 2013 5:19 PM