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DDR3-1600MHz in a 2011 MBPro
- Thread starter Hexley
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The question was exactly what I was about to post : )
What I'd like to know though, is what exactly differentiates the correct 1600 RAM to get? The vendors either don't display what the answer for MBP users is or don't know. IOW, for one, some users are saying that if it's non-XMP RAM it will run at 1600 and not 1333, due to OSX not having editable bios settings. (I know there's not a proven perceivable difference in real world use for the MBP in question, but in some cases there's not much difference in price). When I comparison shop most I can't decipher how to detect this, if indeed the MBP even deals with the difference.
Another question is that the 1600/1333 mhz speeds are generally on chips with 1.35v for the former and 1.5v for the latter, as well as latency rating of 11 on the 1600 and 9-9-9-24 on the 1333mhz. For sake of apples to apples I'm comparing the two on OWC. I would love to be schooled as far as how these two factors, the voltage and latency difference, is something that is relevant or not in a late 2011 2.5Ghz MBP.
Thanks for any info.
Thought the 2011 MBP runs at 1333Mhz, at least that's what it shows me here (I have 2x8GB Corsair 1600Mhz ram)
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Are you on 10.8, 10.7 or 10.6?
I am looking to install 16GB DDR3-1600MHz G.SKILL F3-1600C10D-16GSQ on early and late MBPros with varying Intel Core processors.
Why this specific model? Buying in bulk for discount and to future proof the RAM purchase.
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i'm on 10.8. I only ever use Crucial, just from my own experiences. I've never had a problem with them.
It'll run at 1600MHz. Just make sure you replace both of your RAM sticks at one time - You need to match your RAM's timings, and having two sticks with different timings can result in everything from significantly degraded performance to system instability.
A side note: I have had one case (ever, so far) where RAM did not work in a machine rated for a lower speed than the RAM was. I tried it in a different machine of about the same vintage, and it was fine, so I put that machine's RAM in the one that wasn't working, and that worked too... But apparently it is possible for memory that doesn't match the nominal specs to not work.
It is likely to. Not 100% guaranteed. In general, DDR3 RAM should be backwards compatible, but my default advice would be to use the given spec rather than overshooting it when possible.
Is there any experience out there with the speed difference in real usage between the two in the MBPs in question for 16 gigs? Impossible for the upgrader to tell, since they're going from 4 to 8 or 16 at the same time. It's theoretically very tiny but are there any bench tests to show if it's completely negligible or a small but not negligible difference?
Thanks.
Thanks.
But is there a bottleneck in these MBPs architecture that prevents getting 1600 thoughout the path even though the full amount of Mhz is recognized? IOW, the "get info" is correct but the performance isn't 1600?
Thanks.
Not true, the Sandy Bridge chipset support 1600MHz and 160GB, Apple didnt use it at the time because at the time the SO-DIMMs werent readily available.
Indeed. It will work fine on the 2011 quad core models, but I have only confirmed this with 1600 MHz CL9 RAM.
It makes a small difference when upgrading from 1333 MHz, like 200-300 extra points in Geekbench. Real world difference in apps? Not too much depending on the app. Stuff like Winrar loves faster memory.
Just want to add on that the base model early 2011 (2.0 GHz) only runs at 1333 MHz.
I just want to correct you, only the 2011 13" models run at 1333MHz, ALL 2012 15" and 17" models, base or not run and posts at 1600MHz.
One big (and I mean BIG) problem is that the tech support at the memory vendors are generally clueless about these Mac issues we are hashing over here. So anyone using what they have been told directly from the memory company is bound to have wrong info.
Here's an example from Corsair:
http://forum.corsair.com/forums/showthread.php?p=615898
If a support person said this: "And I would check with Apple on that model if it supports 16 Gig as Apple has stated adamantly that MBP models do not support more than 8 Gig of memory total" in March 2011 it would be one thing, but he said it two weeks ago : ( I don't think Apple has continued to "adamantly" say such a thing in 2012. It's ancient.
And in fact when I was at a Genius Bar last month discussing something else and brought up RAM upgrades EVERYONE told me it was common knowledge that my model (late 2011 2.5 15") would love having 16 regardless of what the outdated posted spec was.
I'm glad I never took the info I got from the vendors I spoke with about the question I posed earlier, about the mhz and voltage differences, seriously. I never did find one who seemed to be doing anything but reading the spec sheets. That's not a big deal for a reseller but this from Corsair I expected more.
Good thing I can count on forums like this one to get decent info to make an informed decision. I appreciate posts from you folks who have done various installs and given your results. Thanks!
Here's an example from Corsair:
http://forum.corsair.com/forums/showthread.php?p=615898
If a support person said this: "And I would check with Apple on that model if it supports 16 Gig as Apple has stated adamantly that MBP models do not support more than 8 Gig of memory total" in March 2011 it would be one thing, but he said it two weeks ago : ( I don't think Apple has continued to "adamantly" say such a thing in 2012. It's ancient.
And in fact when I was at a Genius Bar last month discussing something else and brought up RAM upgrades EVERYONE told me it was common knowledge that my model (late 2011 2.5 15") would love having 16 regardless of what the outdated posted spec was.
I'm glad I never took the info I got from the vendors I spoke with about the question I posed earlier, about the mhz and voltage differences, seriously. I never did find one who seemed to be doing anything but reading the spec sheets. That's not a big deal for a reseller but this from Corsair I expected more.
Good thing I can count on forums like this one to get decent info to make an informed decision. I appreciate posts from you folks who have done various installs and given your results. Thanks!