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tubeexperience

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I asked why the MacBook Pro Retina have soldered RAM. Some replied that having soldered RAM allow the MacBook Pro Retina to be thinner, never mind that there are laptops as thin as the MacBook Pro Retina that have upgradable RAM. I am letting this one slide it now.

So, why does the Mac mini have soldered RAM?

Also, why does the 21.5-inch iMac have soldered RAM?

I can't help but to reason that this was done so that Apple can charge exorbitant upgrade prices at the time of purchase.

After all, Scrooge McDuck ...I mean Tim Cook... needs more money so that he can build another solid gold swimming pool.
 

Maxx Power

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Apr 29, 2003
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All the soldered RAM varieties of iMacs, Mac Minis and Macbooks are using LPDDR3. LPDDR3 doesn't come in SODIMM format at all, as far as I know. The non-soldered RAM varieties use DDR3L/DDR3 and that does come in SODIMM format.

I suspect the choice to go with LPDDR3 sealed the deal for soldered RAM. One of the reasons to go with LPDDR3 is that the 1866 Mhz bins are officially supported by the Intel processors (for example in the MBP), and you can get more performance out of the integrated GPU using faster memory. While you could technically force use DDR3L instead, it isn't supported, as per Intel specifications (look at i7 - 5557U in the 13" MBP, at http://ark.intel.com/products/84993/Intel-Core-i7-5557U-Processor-4M-Cache-up-to-3_40-GHz).

Hence, I suspect future Intel chips are going to use more and more of the LPDDR3/LPDDR4 varieties and due to mobile phones sharing those chips, they might be preferentially developed, but of course, there are no SODIMMs.

That is just one reason, I suspect that Apple has form factor changes (slimming down) in mind down the road and is softening the blow by changing one thing at a time.
 
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tubeexperience

macrumors 68040
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Feb 17, 2016
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All the soldered RAM varieties of iMacs, Mac Minis and Macbooks are using LPDDR3. LPDDR3 doesn't come in SODIMM format at all, as far as I know. The non-soldered RAM varieties use DDR3L/DDR3 and that does come in SODIMM format.

I suspect the choice to go with LPDDR3 sealed the deal for soldered RAM. One of the reasons to go with LPDDR3 is that the 1866 Mhz bins are officially supported by the Intel processors (for example in the MBP), and you can get more performance out of the integrated GPU using faster memory. While you could technically force use DDR3L instead, it isn't supported, as per Intel specifications (look at i7 - 5557U in the 13" MBP, at http://ark.intel.com/products/84993/Intel-Core-i7-5557U-Processor-4M-Cache-up-to-3_40-GHz).

Hence, I suspect future Intel chips are going to use more and more of the LPDDR3/LPDDR4 varieties and due to mobile phones sharing those chips, they might be preferentially developed, but of course, there are no SODIMMs.

That is just one reason, I suspect that Apple has form factor changes (slimming down) in mind down the road and is softening the blow by changing one thing at a time.

The difference between LPDDR3 and DDR3L is that the former has lower standby standby power.

LPDDR3 doesn't provide much benefit to Mac mini and iMac users since neither of these devices run on battery.
 

Maxx Power

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Apr 29, 2003
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The difference between LPDDR3 and DDR3L is that the former has lower standby standby power.

LPDDR3 doesn't provide much benefit to Mac mini and iMac users since neither of these devices run on battery.

I agree there isn't a large amount of benefit, and I never stated such. I was simply pointing out that if you wanted to support the fastest implementation of current Intel chips used - you go with LPDDR3 and not DDR3L. The benefit of the LPDDR3 is at the present - 1866 Mhz memory vs. 1600 on the DDR3L. The integrated GPUs in these machines benefit from the increased RAM speed.

I also think that in the future, Intel will gradually transition a lot of their mobile chips to LP-RAM.
 

tubeexperience

macrumors 68040
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Feb 17, 2016
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I agree there isn't a large amount of benefit, and I never stated such. I was simply pointing out that if you wanted to support the fastest implementation of current Intel chips used - you go with LPDDR3 and not DDR3L. The benefit of the LPDDR3 is at the present - 1866 Mhz memory vs. 1600 on the DDR3L. The integrated GPUs in these machines benefit from the increased RAM speed.

I also think that in the future, Intel will gradually transition a lot of their mobile chips to LP-RAM.

That's not true at all. The 27-inch iMac has 1866 MHz memory and the RAM is upgradable.

In fact, there are a bunch of DDR3L 1866 memory on newegg and other sites.
 

Maxx Power

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That's not true at all. The 27-inch iMac has 1866 MHz memory and the RAM is upgradable.

You are not comparing the equal year models - the early and mid 2015 models of the iMacs did not have 1866 Mhz memory - following Intel specifications. The CPUs used in the MBPs, Mac Minis and base 21.5 inch iMacs are from the Broadwell generation and before, the CPUs used in the 27 inch iMacs are the newest Skylake variety - entirely different memory controllers.

EDIT: I should mention that the 4K iMac is still Broadwell, but with 1866 Mhz DDR3L - because it is supported as per Intel specifications. Other Broadwell/Haswell chips used in Apple's machines only specified 1866 Mhz LPDDR3.
 
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tubeexperience

macrumors 68040
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Feb 17, 2016
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You are not comparing the equal year models - the early and mid 2015 models of the iMacs did not have 1866 Mhz memory - following Intel specifications. The CPUs used in the MBPs, Mac Minis and base 21.5 inch iMacs are from the Broadwell generation and before, the CPUs used in the 27 inch iMacs are the newest Skylake variety - entirely different memory controllers.

I am looking at Intel Core i5-5675R (Broadwell).

It said right under specification that it supports DDR3L-1866.

http://ark.intel.com/products/87715
 

Maxx Power

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Apr 29, 2003
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Okay. That's not a limitation since Apple gets to choose the chips.

You can't choose the most expensive chips possible AND desktop chips for use in the lowest equipped iMac and Mac Minis, not to mention, you can't physically stick those chips in the MBPs.

EDIT: I should quantify my statement by saying that the desktop i5 and i7 chips from Broadwell support 1866 Mhz DDR3L, but they all feature Iris Pro GPUs (the ONLY desktop chips ever released from the Broadwell generation). It just does not seem likely that Apple (or anyone else) would toss these chips into their lowest tier products.
 
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tubeexperience

macrumors 68040
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Feb 17, 2016
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You can't choose the most expensive chips possible AND desktop chips for use in the lowest equipped iMac and Mac Minis, not to mention, you can't physically stick those chips in the MBPs.

Do you even realize that those chips don't even use the same "socket"?

(I put "socket" in quotation because BGA isn't really a socket)
 

Maxx Power

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Apr 29, 2003
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Do you even realize that those chips don't even use the same "socket"?

(I put "socket" in quotation because BGA isn't really a socket)

You don't have to speak in that condescending way - I am 100% aware that these chips use Ball Grid Array while the other desktop chips traditionally use Pin Grid Array or Land Grid Array. None of that changes the fact that these are desktop chips with 65 Watt TDPs and Iris Pro GPUs, making them unsuitable for entry-level computers.

I am here to make positive contributions to your thread, please keep that in mind.
 

tubeexperience

macrumors 68040
Original poster
Feb 17, 2016
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EDIT: I should quantify my statement by saying that the desktop i5 and i7 chips from Broadwell support 1866 Mhz DDR3L, but they all feature Iris Pro GPUs (the ONLY desktop chips ever released from the Broadwell generation). It just does not seem likely that Apple (or anyone else) would toss these chips into their lowest tier products.

The 27-inch iMac 5K has the Intel Core i5-6500 and Intel Core i5-6600 which supposedly don't support DDR3L 1866MHz, yet somehow the 27-inch iMac 5K has DDR3L 1866MHz anyway.

http://ark.intel.com/products/88184

http://ark.intel.com/products/88188

This basically invalidates your entire argument.
 

Maxx Power

Cancelled
Apr 29, 2003
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The 27-inch iMac 5K has the Intel Core i5-6500 and Intel Core i5-6600 which supposedly don't support DDR3L 1866MHz, yet somehow the 27-inch iMac 5K has DDR3L 1866MHz anyway.

http://ark.intel.com/products/88184

http://ark.intel.com/products/88188

This basically invalidates your entire argument.

It doesn't at all - as you can easily see that Apple designs each generation of hardware differently and thus validation and testing is done per generation. No DDR3L 1866Mhz was used for the non-supporting chips in the Broadwell/Haswell generation, which was your biggest gripe. While Apple doesn't share their validation data with the public - I would think the Skylake generation obviously paired well with the 1866 Mhz DDR3L in Apple's testing, or they were able to work something out with Intel.

In addition, I remembered now that if you shopped around for 1866 or 2133 Mhz DDR3L during the days of Haswell, you'd know they were hard to come by as they just entered the market after Haswell.
 

tubeexperience

macrumors 68040
Original poster
Feb 17, 2016
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It doesn't at all - as you can easily see that Apple designs each generation of hardware differently and thus validation and testing is done per generation. No DDR3L 1866Mhz was used for the non-supporting chips in the Broadwell/Haswell generation, which was your biggest gripe. While Apple doesn't share their validation data with the public - I would think the Skylake generation obviously paired well with the 1866 Mhz DDR3L in Apple's testing, or they were able to work something out with Intel.

So after I invalidated your entire argument, you are now trying to defend it using pure assumption?
 

Maxx Power

Cancelled
Apr 29, 2003
861
335
The 27-inch iMac 5K has the Intel Core i5-6500 and Intel Core i5-6600 which supposedly don't support DDR3L 1866MHz, yet somehow the 27-inch iMac 5K has DDR3L 1866MHz anyway.

http://ark.intel.com/products/88184

http://ark.intel.com/products/88188

This basically invalidates your entire argument.

I forgot to mention there are oddities to the first generation Skylake processors - their memory controllers are not well documented. Some motherboards allow DDR3 (non-L) and others forbid DDR3L. Intel has said the chips do not operate well with 1.5V DDR3, but then testing shows that they are okay.
[doublepost=1467357244][/doublepost]
So after I invalidated your entire argument, you are now trying to defend it using pure assumption?

Absolutely NOT. On your side of the argument - you assume whatever is true for the Haswell/Broadwell generation is necessarily true for the Skylake generation - I am pointing out that the testing may NOT have come to the same conclusion, given that the underlying chips have changed. Why should 1866 Mhz DDR3L memory be found to be equally happy in Haswell as it is in Broadwell and Skylake? Obviously parameters changed as time went on.
 
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tubeexperience

macrumors 68040
Original poster
Feb 17, 2016
3,192
3,897
I forgot to mention there are oddities to the first generation Skylake processors - their memory controllers are not well documented. Some motherboards allow DDR3 (non-L) and others forbid DDR3L. Intel has said the chips do not operate well with 1.5V DDR3, but then testing shows that they are okay.
[doublepost=1467357244][/doublepost]

Absolutely NOT. On your side of the argument - you assume whatever is true for the Haswell/Broadwell generation is necessarily true for the Skylake generation - I am pointing out that the testing may NOT have come to the same conclusion, given that the underlying chips have changed. Why should 1866 Mhz DDR3L memory be found to be equally happy in Haswell as it is in Broadwell and Skylake. Obviously parameters changed as time went on.

Maybe DDR3L 1866 MHz works well with Broadwell.

How do I know this?

I don't, but since you are making assumptions, I am making some of my own too.
 

Maxx Power

Cancelled
Apr 29, 2003
861
335
Maybe DDR3L 1866 MHz works well with Broadwell.

How do I know this?

I don't, but since you are making assumptions, I am making some of my own too.

The fact is - 1866 Mhz DDR3L works well in 27 inch iMacs on Skylake (as per Apple).

This CAN NOT be generalized retroactively to indicate that it must work well on Broadwell and Haswell.

These two statements I make are NOT assumptions.

EDIT: I believe you may have confused my digressions of a plausible scenario with an assumption. I digressed to hypothesize that Apple may have different validation results, leading to our observed outcome. It is not a necessary ingredient in my statement, just a digression.

[doublepost=1467358059][/doublepost]
Maybe DDR3L 1866 MHz works well with Broadwell.

How do I know this?

I don't, but since you are making assumptions, I am making some of my own too.

Since you mention, I use DDR3L 1866 Mhz on my Broadwell laptop with i5 - 5700 Hq. It works well. I use DDR3L 1866 Mhz ram on my desktop with Ivy Bridge Xeon. Neither is officially supported, but that's OKAY, as I do my own memory tests for days on end to validate the memory. I don't have that expectation on Apple or others and I DO NOT claim that my two sample points equates general compatibility.
 
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tubeexperience

macrumors 68040
Original poster
Feb 17, 2016
3,192
3,897
The fact is - 1866 Mhz DDR3L works well in 27 inch iMacs on Skylake (as per Apple).

This CAN NOT be generalized retroactively to indicate that it must work well on Broadwell and Haswell.

You stated it as a definitely fact that those Broadwell chips do not work with DDR3L 1866 MHz.

Somehow, I don't think you are a computer engineer working at Apple, who can verify this as fact.

Since you mention, I use DDR3L 1866 Mhz on my Broadwell laptop with i5 - 5700 Hq. It works well. I use DDR3L 1866 Mhz ram on my desktop with Ivy Bridge Xeon. Neither is officially supported, but that's OKAY, as I do my own memory tests for days on end to validate the memory. I don't have that expectation on Apple or others and I DO NOT claim that my two sample points equates general compatibility.

So you concede that your "facts" might be wrong?
 
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