I have looked into this with some depth and there are multiple factors involved, but among them are the Intel 950 and 965 controller and the available densities of DRAM for MacBooks, et. al., in a Single Channel configuration, which is how these machines are equipped.

I have looked at most manufacturers of note, online, and while there are 4GB and 8GB FB-DIMMS (in single and dual channel) there are no SINGLE CHANNEL SO-DIMMS available above 2GB. I refer to both stick mfgrs and DRAM mfgrs.

There are a few Dual Channel 4GB 200 pin SO-DIMMs out there, AND Kingston apparently makes one (4GB x2 = 8GB kit), but they don't advertise it on their site despite the having the model number. And the density is 512x64. It's also (it's PC6400) - but it doesn't yet exist in any numbers even at the manufacturer.

They have a list price of $940, but I've seen places that only want $100, but not in stock.

If these are dual channel units, they are NOT going to work in anything that Apple has out. Only the FB-DIMMs will work in the MacPro towers -- otherwise, until the next memory controller comes along -- Intel specifically states DUAL CHANNEL in the document referenced below, to get to 8GB - so I don't know who is testing what -- but if the Intel parts don't want to see above 4GB in Single Channel Mode (and there is real argument as to whether they do ANYWAY - check your Activity Monitor and do the math) - I don't know how anyone is testing any 4GB modules (x2) in any Macintosh units.

I was around it long enough in 2006 and 2007, and I was never aware of any such testing, and it was partly my business & my desire to know. These things typically aren't done in secret, anymore than was the testing of the first pair of 2.4GHz Clovertowns (4 cores each) in a day old Intel MacPro that only had dual core CPUs.

Your milage may vary - and there certainly are going to be things out there I'm unaware of, but I'm focusing on just 4GB modules for the MacBook / MacBook Pro - and while they could have been custom made, seems analogous stuffing an engine into a car with bicycle tires. Can't put the power to the road - cause their isn't enough rubber to do it.

In this case, rubber equals the channel breadth. The CONTROLLER can go to 8GB, but not with single channel sockets, of which the Mac has a pair of SINGLES. I have yet to see a 4GB that is not dual channel, but would try it out in an instant if I could find the units.

My first guess is that this is intentional - because 8GB laptops will be the next great thing to upgrade to.

Even direct reference to the Samsung factory assembled parts TESTED BY INTEL will only Google you right back to the document that details testing the DRAM with the family of controllers.

If you find one and it works - even just ONE, I'd like to know about it. Otherwise, sounds pipe-dreamish - since it looks to me like it wasn't designed to deal with it in the first place.

[www.intel.com]

(Samsung M470T5267AZ3-CE7 / Samsung K4T4G274QA-TCE7 4GB )

[www.ec.kingston.com]

[dealspl.us]

This is largely academic, even if the sticks were available. I never have "enough" RAM in my Macs because it often takes crazy dollars to max them out. I had to think twice about spending $100 for RAM on a $500 mini, but did it in the end.

So I will NOT lament being stuck to my mini only seeing 3.3GB of RAM. That's already double what my Dual G5 has, because when I bumped that one up to 1.5GB years ago I had to spend $200 to do so, and by the time RAM prices for it came down (haven't looked but I assume they have) I no longer want to spend money on the box.

Computers are a sum of all their parts, and there's a very valid reason why the Mac Pro can take more RAM than the others.

Its pretty much as I was expecting. yes, it would be great to put 8GB in the machine I have now. (and I certainly would if the price was near reasonable)

i guess i'll need to upgrade when apple releases a MBP that can take 8GB of ram. i have to admit that i won't hesitate, although i may wait for refurbs.

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deckeda

Computers are a sum of all their parts, and there's a very valid reason why the Mac Pro can take more RAM than the others.

Point here being that there was discussion of having tested workable SODIMMs that were fine, but "ran hot." And unless they were magical SODIMMs, blessed by Intel, and put on Single Channel sticks that defy binary mathematics, I don't see how that trial could have taken place.

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The market just isn't that big.

Windows can't use more than 4GB. (except for the 64-bit versions of Vista that don't have much driver support)

grm.....ITS WINDOW'S FAULT

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great research and nice fact digging

OWC larry was the one that alluded to the 8 gig limit in AL imacs and santa rosa/penryn macbooks/macbook pros and that he had been testing them

i said "a year from now" -- he said "by years end" for the tech to catch up

interested in what he has to say

as for your mini deck, it will never see more than 3.3....

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Edited 999 time(s). Last edit at 12:08PM by jdc.

We have built and tested 4GB 200 Pin SO-DIMMs built with currently available memory device options. The issue currently remains one of heat. The devices are a little thicker and reduce airflow + the memory 'bay' in the the Macbook and MAcbook Pro don't really have much heat dissipation to begin with. In load testing, the extra memory performs nice until the whole system shuts down - not the memory causing it directly, heat building in the system in general.

Possible yes - future forward likely - yes... when the higher density memory is thinner (to maintain the very limited air cooling in the memory bay) and more efficient in terms of using less power, creating less heat.

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OWC Larry
Other World Computing
[www.macsales.com]