Mac Pro RAM Advice

jeffhopkins

macrumors newbie
Original poster
Aug 29, 2012
4
0
Hey, I'm new to this forum, please let me know if this is the wrong place to post this request.

I'm looking to increase/upgrade my RAM. I've got a:

Mac Pro 2X3 GHz Quad-Core Intel Xeon from 2007
Model A1186 8 Memory Slots

(More info in attachment)

It says the max RAM allowed is 32 GB. Is that indeed the limit?
Also, if I were to upgrade RAM, what type should I purchase?

Thanks very much.

Jeff
 

Attachments

GGJstudios

macrumors Westmere
May 16, 2008
44,419
757
I've got a:

Mac Pro 2X3 GHz Quad-Core Intel Xeon from 2007
Model A1186 8 Memory Slots

(More info in attachment)

It says the max RAM allowed is 32 GB. Is that indeed the limit?
Yes, it is. You can find specs on all Apple products, including maximum RAM:
Also, if I were to upgrade RAM, what type should I purchase?
Some great sources for RAM are OWC, Crucial and newegg.com.
 

paulrbeers

macrumors 68040
Dec 17, 2009
3,960
120
Hey, I'm new to this forum, please let me know if this is the wrong place to post this request.

I'm looking to increase/upgrade my RAM. I've got a:

Mac Pro 2X3 GHz Quad-Core Intel Xeon from 2007
Model A1186 8 Memory Slots

(More info in attachment)

It says the max RAM allowed is 32 GB. Is that indeed the limit?
Also, if I were to upgrade RAM, what type should I purchase?

Thanks very much.

Jeff
To answer your question, you are looking for 667mhz DD2 FBDIMM with "big" heatsinks (not the thin ones that you generally see). You may want to consider checking eBay for used Mac Pro RAM. It's cheaper and if your Mac Pro dies any time soon you won't be so upset you got so "little" time with your expensive RAM. If you want to go new, and are in the US then consider OWC (macsales.com).
 

spoonie1972

macrumors 6502a
Aug 17, 2012
547
47
Toronto
i had good luck with memorydepot.com for the FB-DIMMS on the 2008 (the ones w/ the giant heatsinks). 800mhz. should work just as well in 667 speed.

Not cheap.
 

jeffhopkins

macrumors newbie
Original poster
Aug 29, 2012
4
0
Follow Up Question: I've purchased 16 Gb RAM (4 x4). My machine has 8 slots. Four of them are filled with 2 Gb RAM chips. Can I fill the rest with my new RAM to make 24 Gb? Or do they all have to be the same amount?

Thanks again for all your help.

Jeff
 

ColdCase

macrumors 68030
Feb 10, 2008
2,972
145
NH
So it doesn't matter for a 2007? No memory bus width issue, if that makes any difference. What about recognizing all the RAM? I've always heard you could mix RAM sizes, but there are optimum slots to place the RAM on the risers. Maybe that was the case for the 2008s.
 

phpmaven

macrumors 68040
Jun 12, 2009
3,397
450
San Clemente, CA USA
They don't need to be. There is a slight benefit to using matched pairs, but that benefit isn't outweighed by having more RAM, even if it's not in matched pairs.

MR Guide to Matched RAM on Intel Macs
While that may technically be true, if you are going to have a large amount of RAM, say 24GB or more, having a mismatched pair is probably going to hurt more than the help you would get from the extra RAM. The linked article mentions a small amount of RAM where one stick might be 2GB and the other 1GB. The article is also based on info from 6 years ago.

I would stick with matched pairs.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,419
757
While that may technically be true, if you are going to have a large amount of RAM, say 24GB or more, having a mismatched pair is probably going to hurt more than the help you would get from the extra RAM.
Having mismatched pairs doesn't hurt at all; it just doesn't have the slight extra advantage of matched pairs. Adding a mismatched pair will have no effect on the existing matched pairs already in use.