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32GB (2x16GB) not yet being sold?

post #1 of 20
Thread Starter 

I noticed that some laptops with mobile Core i5 and Core i7 can handle 32GB but because some laptops only have two memory slots they can only get to this memory size by two 16GB SODIMM modules.

Would anyone have an idea when these will be sold?

And please, no "what do you need a 32GB in a laptop for?" questions.

post #2 of 20

I don't believe the sticks exist yet, is all.

 

Remember, 640k ought to be enough for anyone. 1wink.gif

post #3 of 20
You will probably not see 16 GB SODIMMS until DDR4.
post #4 of 20
Thread Starter 

It appears that (2x16GB) 32GB will become available as a DDR3-1866 module by the time Intel Haswell starts shipping. CORSAIR and Kingston are already selling smaller capacity modules at that speed.

post #5 of 20
Quote:
Originally Posted by As Seen on TV View Post

It appears that (2x16GB) 32GB will become available as a DDR3-1866 module by the time Intel Haswell starts shipping. CORSAIR and Kingston are already selling smaller capacity modules at that speed.

How do you figure? RAM speed is different from RAM capacity. I have seen 16 GB DIMMS though not SODIMMS.
post #6 of 20
Thread Starter 
Quote:
Originally Posted by Winter View Post


How do you figure? RAM speed is different from RAM capacity. I have seen 16 GB DIMMS though not SODIMMS.


Demand for higher density modules is more with desktops than mobile.

post #7 of 20
Quote:
Originally Posted by As Seen on TV View Post


Demand for higher density modules is more with desktops than mobile.

That, and it might be because there's only so much board area to put chips. A bigger DIMM is going to fit more or bigger chips.
post #8 of 20
Given that Ivy Bridge can handle a max of 32 GB of RAM, I would like to have a 2 x 16 GB setup even though I am not even using the 8 GB I have now in my 2011 Mac mini. If a 32 GB option were available for the Mac mini and 15" MacBook Pro, I can only imagine what Apple would charge for it.
post #9 of 20
Quote:
Originally Posted by Winter View Post

Given that Ivy Bridge can handle a max of 32 GB of RAM, I would like to have a 2 x 16 GB setup even though I am not even using the 8 GB I have now in my 2011 Mac mini. If a 32 GB option were available for the Mac mini and 15" MacBook Pro, I can only imagine what Apple would charge for it.

I think it might work, but as yet, I've not seen any such SODIMMs available yet. Often, a machine is capable of more than what Apple says, but if a size isn't available in good quantity to test, they don't claim it's capable.

I don't know if it's worth getting 4x what you think you need. It might be cheaper to get 2x what you need, and if/when you need to expand again, the additional 2x will probably be a LOT cheaper by then, and you replace your memory at that time.
Edited by JeffDM - 12/16/12 at 5:30pm
post #10 of 20
Yeah I don't feel like spending the money for the 16 GB and if a 2x16 setup were possible, I probably would not take advantage until it was about as cheap as 2x8 is now.
post #11 of 20

32GB in a notebook remains a specialty use case today. It's basically covered by the "mobile workstation" variants as many of them can take 4 sodimms.  I'm not talking about the ones that cram in desktop parts. There are several that are simply beefy notebooks in the 6 pound range. It's even a specialty case on Windows, as desktops remain a better overall fit for those kinds of requirements. Supposedly 32GB works on Sandy as well. It's just unlikely that we'll see any 16GB sodimms that are compliant with Ivy Bridge. For desktops and workstations, I've seen them down to a little over $200. I doubt they're incredibly popular. You can get to 32GB on a single package workstation with 8GB dimms. A 12 core workstation can get to 64 GB without the use of 16GB dimms. At that level, it is possible to consume that amount of memory with highly parallel tasks. I still get pageouts at 16GB on my notebook. The ssd helps alleviate that somewhat. I meant it helps alleviate the speed hit.

post #12 of 20
I won't be buying an Ivy Bridge computer. I will be buying either a Haswell computer or possibly even a Rockwell computer (which might be DDR4 by that time).

By then I'll either have a Mini (next year) or possibly even an iMac or Mini (2014).
post #13 of 20
Quote:
Originally Posted by Winter View Post

I won't be buying an Ivy Bridge computer. I will be buying either a Haswell computer or possibly even a Rockwell computer (which might be DDR4 by that time).
 

At least intel will be somewhat more up to date with OpenCL/OpenGL framework support by that time. They've been playing catch up for several years at this point. It was definitely needed given the trend toward further levels of integration. Anandtech has a nice article on Haswell in case you're interested.

post #14 of 20
You meant by Haswell time, correct? Not Rockwell?
post #15 of 20
Quote:
Originally Posted by Winter View Post

You meant by Haswell time, correct? Not Rockwell?


Somehow I missed this. Yes I meant Haswell.

post #16 of 20
Quote:
Originally Posted by Tallest Skil View Post

 

Remember, 640k ought to be enough for anyone. 1wink.gif

 

There is no reason anyone would want a computer in their home.

post #17 of 20

When I last looked into this because I use tons of RAM for my virtual machines at work, there were challenges with timing or something along those lines as such it was stated there would be no DDR3 16 gig modules we would have to wait for DDR4 to get modules of that density. However things are always changing and it might be possible with DDR3 now.

post #18 of 20

Intelligent Memory is making them!  

 

http://www.intelligentmemory.com/dram-modules/ddr3-so-dimm/

post #19 of 20
Quote:
Originally Posted by libertyforall View Post

Intelligent Memory is making them!  

http://www.intelligentmemory.com/dram-modules/ddr3-so-dimm/

"Sampling" - meaning very limited supply and it would probably only go to preferred customers, and the final customer would probably paying a very high price.
post #20 of 20

Hi!

 

the 16GB DDR3 SO-DIMMs from Intelligent Memory (www.intelligentmemory.com) are orderable, price around $300 each, but the problem is: They most-likely won't boot on Apple systems due to a software-issue

 

The root-cause is going back to Intel.

Back in year 2007 the JEDEC committee created the DDR3 memory standard. Intel was part of that team. The JEDEC DDR3 standard defines the exact functionality, pinouts and possible chip-capacities of DDR3 components. Per this specification called JESD79-3 a DDR3 memory-chip can have up to 8 Gigabit (= 1GB per chip!). The Intelligent Memory 16GB UDIMM and SO-DIMM modules are made of 16 pcs of these chips.

8GB unbuffered DIMM / SO-DIMM modules are made of 16 Chips of 4Gbit each

16GB unbuffered DIMM / SO-DIMM modules are made of 16 Chips of 8Gbit each

 

Since Intel was part of the JEDEC group defining this DDR3 standard, it could be expected that Intel also supports all memory capacities on their CPUs -> up to max 8 Gigabit per DRAM-IC, up to 16GB per UDIMM/SO-DIMM.

 

From a hardware point-of-view, a 4 Gigabit DDR3 chip uses the same physical address and control lines as a 8 Gigabit DDR3 chip. Therefore 'in theory' any CPU that can take unbuffered DIMM or SO-DIMM modules with 8GB should also have no issue to take 16GB modules.

But this is just the hardware side!

 

Now let us look at the software-side of the story:

When you start your system, it begins loading the BIOS (on Apple it is called UEFI) from a Flash-chip on the board and executes it. One of the first parts of this BIOS/EFI is the Memory Reference Code, short called MRC.  The MRC has the job to read out the SPD-data (serial presence detect information) from the memory modules installed on the board. Byte #4 of the SPD-data contains the memory component density.

The MRC software has a limitation exactly at this point. If it reads SPD Byte #4 and finds that there are memory-chips on the module with a capacity larger than 4 Gigabit per chip, it does not know what to do. The programmer of the MRC just did not include any code to handle 8 Gigabit DDR3 chips ---> the system hangs during boot!

 

This issue is reproducable with about every Intel CPU based system. Only for the Atom C2000, codename 'Avoton', Intel has fixed this.

 

Intel would eventually do a modification of the MRC code when enough people start complaining to them. If the company Apple itself talked to Intel and wishes to get this changed, it will most-likely be checked and corrected very quickly, a new BIOS or UEFI would be released and every Apple user could use 16GB modules.

But how can we push Apple to look at this? Maybe Apple is able to change the memory reference code on their own, even without having to ask for Intels help?

 

FYI: The famous company ASUS has done the modification of the Memory Reference Code on their own for one of their motherboards (X79 with Ivybridge E Intel i7 CPU) and reported that they are working fine now. This shows that it is possible in general!

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