Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

seoartinfo

macrumors newbie
Original poster
Feb 3, 2007
11
0
i want to change and increase my Ram capacity, how do i install it. looking for instructions thanks.
 

CanadaRAM

macrumors G5
First step: Check the owners manual that came with your machine

There are 2 riser cards in the machine which pull out. There are 4 memory sockets on each riser card. RAM must be installed in pairs. You install RAM in Sockets 1 and 2 on the one riser, then sockets 1 and 2 on the other riser.
 

seoartinfo

macrumors newbie
Original poster
Feb 3, 2007
11
0
canada ram

thank you very much for your expertise, i will follow the instructions.
 

twoodcc

macrumors P6
Feb 3, 2005
15,307
26
Right side of wrong
First step: Check the owners manual that came with your machine

There are 2 riser cards in the machine which pull out. There are 4 memory sockets on each riser card. RAM must be installed in pairs. You install RAM in Sockets 1 and 2 on the one riser, then sockets 1 and 2 on the other riser.

so is it better to have 4 on one riser, or 2 on both?
 

AaronICT

macrumors member
Feb 8, 2007
92
0
so is it better to have 4 on one riser, or 2 on both?

The instructions are silkscreened on the INSIDE of the case. There is a specific order you have to install the pairs.

Two top, then two bottom, then two more on top, then two more on bottom. Look at the picture inside your machine.
 

twoodcc

macrumors P6
Feb 3, 2005
15,307
26
Right side of wrong
The instructions are silkscreened on the INSIDE of the case. There is a specific order you have to install the pairs.

Two top, then two bottom, then two more on top, then two more on bottom. Look at the picture inside your machine.

it doesn't say you have to. right now i have 4 on the top, 0 on the bottom.

i thought i read somewhere that you have to have 4 to reach the 256 whatever
 

dkoralek

macrumors 6502
Sep 12, 2006
268
0
it doesn't say you have to. right now i have 4 on the top, 0 on the bottom.

i thought i read somewhere that you have to have 4 to reach the 256 whatever

You have to have four dimms populated to get quad channel (but not four on one riser). You will get better throughput, I would imagine, by having them split over the two risers, rather than full on one and empty on the other.

cheers.
 

twoodcc

macrumors P6
Feb 3, 2005
15,307
26
Right side of wrong
You have to have four dimms populated to get quad channel (but not four on one riser). You will get better throughput, I would imagine, by having them split over the two risers, rather than full on one and empty on the other.

cheers.


thanks.

can anyone confirm? the only reason i ask is that i thought i read somewhere that it was better to have 4 on one riser, but maybe i am mistaken
 

Sun Baked

macrumors G5
May 19, 2002
14,941
162
thanks.

can anyone confirm? the only reason i ask is that i thought i read somewhere that it was better to have 4 on one riser, but maybe i am mistaken

No, the memory is switched.

There are four memory channels spread over two risers (each riser having its own dual channel memory controller) making all the 1&2 DIMMs, or all the 3&4 DIMMs, work at the same time.

Putting everything on one risers cuts you back from a quad memory channel machine to a dual -- and increases latency every time the memory controller for the riser changes from one bank of DIMMs to another.
 

amtctt

macrumors regular
Sep 8, 2006
135
0
thanks.

can anyone confirm? the only reason i ask is that i thought i read somewhere that it was better to have 4 on one riser, but maybe i am mistaken

No, you do not want them all on 1 riser. very bad. I think it says right in the manual. it goes 2 on top, then 2 on the bottom, then you can go back to the top if you have more. I have 2x512 on top and 2x512 on the bottom, works great.
 

ljones

macrumors regular
Oct 2, 2006
232
0
Atlanta, GA
On the inside panel of the mac Pro is tells you the order. I have 2 in the bottom, added 2 to the top riser when i installed more ram.

Well actually my 1 gigs are on the bottom, and the 512s are on the top. I switched the order around. This has been discussed many times in multiple forums.
 

TheSpaz

macrumors 604
Jun 20, 2005
7,032
1
Okay, so I have 2x512MB modules on the top and 2x1GB modules on the bottom... this is the correct way to have it? Should the bigger RAM modules be on top or does it not matter since both risers are accessed at the same time?
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.