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sammyman

macrumors 6502a
Original poster
Mar 21, 2005
998
66
Can anyone guess how much faster Sand Bridge iMacs will be whenever they are released? I heard that there are some fast graphics integrated. Are there any other great advantages to the new chipset?
 
The IGP is irrelevant as all iMacs should have a discrete GPU. As for CPU performance, my guess is 10-20%
 
The IGP is irrelevant as all iMacs should have a discrete GPU. As for CPU performance, my guess is 10-20%

10-20% and the possibility of Light Peak... Trying to figure out if the Mac Pro is still the way to go, or should I wait for updated iMacs? Decisions, decisions.
 
Can we put 32GB in an iMac when it gets Sandy Bridge? Or can we put in faster RAM?
 
If you need to put 32GB of RAM in anything - it's not going to be an iMac, is it?
 
If you need to put 32GB of RAM in anything - it's not going to be an iMac, is it?

Yeah I wouldn't put 32gb in there. I was just thinking future proofing. Thought maybe sandy bridge may bump up the 16gb to 32gb. Just curious.
 
It's possible but unlikely IMO. The current memory controller in iMacs only supports 16GB of RAM and I doubt that Intel will raise that value for mainstream SBs. Besides, You would have to use 8GB modules that basically do not exist at the moment.
 
I thought mac os already supports 32gb ram. it's just how much ram apple decides to put in. I am pretty sure if you are willing to buy 4*8gb you can see mac os is able to recognize it.
 
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I am not sure about that statement regarding RAM... Not sure, but I think some Macs are limited, not only by the number of RAM slots.
 
ram capacity is built into the OS. just like the window's jump from 32bit to 64bit so that the system can draw on more than 4gb ram. mac pro supported up to 64gb ram, and so should other mac system. the imac can use 32gb ram and 64gb if you really have the money.

edited: i found that the max you can put in an imac is 32 while for mac pro is 64. that's because of physical limitation. as for the system, 64gb ram is no problem
 
I can think of four computer bits that can limit the RAM that is useable:

1) The number/type of slots. As iMacs have only 2 (I think) and Mac Pros have up to 8 (I think) it's kind of silly to compare them. If you can only buy 4GB RAM modules, then you can only put 8GB in an iMac. If 8GB modules are available, then 16GB is possible, etc.

2) The memory controller. This is why sometimes 8 GB won't work in some computers (ie. some MBPs), but 6 will, for example.

3) The CPU. 32 bit CPUs could only recognise 4 GB of RAM (ie. 2^32 bytes). Now that we're using 64 bit CPUs, that limit is irrelevant for the foreseeable future (ie. 16 million TB).

4) The OS. If you run a 32 bit OS on a 64bit CPU, you'll still only be able to use 4GB of RAM. I think. Maybe each app is limited to 4 GB instead. Not sure. But Snow Leopard is 64 bit, so same deal as with the CPU. Stupidly high ceiling.
 
I thought mac os already supports 32gb ram. it's just how much ram apple decides to put in. I am pretty sure if you are willing to buy 4*8gb you can see mac os is able to recognize it.

64-bit OS X supports up to 16EBs of RAM. That is 16 000 000 000GB.

Today’s Mac computers can hold up to 32GB of physical memory, but the 32-bit applications that run on them can address only 4GB of RAM at a time. 64-bit computing shatters that barrier by enabling applications to address a theoretical 16 billion gigabytes of memory, or 16 exabytes.

http://www.apple.com/macosx/technology/

1) The number/type of slots. As iMacs have only 2 (I think) and Mac Pros have up to 8 (I think) it's kind of silly to compare them. If you can only buy 4GB RAM modules, then you can only put 8GB in an iMac. If 8GB modules are available, then 16GB is possible, etc.

Current iMacs have four RAM slots. Yes, even the 21.5". Only DP Mac Pro has 8 slots, SP versions come with four slots like iMacs.

You can already put 16GB in iMac (4x4GB)

2) The memory controller. This is why sometimes 8 GB won't work in some computers (ie. some MBPs), but 6 will, for example.

Memory controller or the firmware. Apple is infamous of its firmwares that limit things.

3) The CPU. 32 bit CPUs could only recognise 4 GB of RAM (ie. 2^32 bytes). Now that we're using 64 bit CPUs, that limit is irrelevant for the foreseeable future (ie. 16 million TB).

32-bit CPUs (at least Core Duos) can only utilize 2GB of RAM.

4) The OS. If you run a 32 bit OS on a 64bit CPU, you'll still only be able to use 4GB of RAM. I think. Maybe each app is limited to 4 GB instead. Not sure. But Snow Leopard is 64 bit, so same deal as with the CPU. Stupidly high ceiling.

That's a Windows thing. OS X has been able to utilize +4GB of RAM for years, even though it was 32-bit. 32-bit apps are limited to 4GB per app.
 
4) The OS. If you run a 32 bit OS on a 64bit CPU, you'll still only be able to use 4GB of RAM. I think. Maybe each app is limited to 4 GB instead. Not sure. But Snow Leopard is 64 bit, so same deal as with the CPU. Stupidly high ceiling.

OS X has been 64-bit since Leopard, but it runs in 32-bit mode by default on most Macs. it can still address up to 16 or 32GB (via PAE) before you have to switch to the 64-bit kernel.

That's a Windows thing. OS X has been able to utilize +4GB of RAM for years, even though it was 32-bit. 32-bit apps are limited to 4GB per app.

I thought 32-bit Windows was limited to 3GB... it just shows 4GB in the system properties so the manufacturers can continue ripping off their customers :rolleyes:

at least for XP and Vista, dunno about 7.
 
I believe you are incorrect. 3GB works. Hence the limit is up to (but not including) 4GB of RAM.

False.

http://www.everymac.com/systems/apple/macbook_pro/faq/macbook-pro-maximum-ram-capacity.html

I think you're confusing Core Duo MBPs with first gen Core 2 Duos

http://www.everymac.com/systems/app...ore-2-duo-3-gb-memory-limitation-details.html

toxic said:
I thought 32-bit Windows was limited to 3GB...

That's exactly what I said. 32-bit Windows is limited to ~3GB but OS X has no such limit.
 
I think that's a limitation of the memory controller on a Core Duo, and Core 2 Duo processor. Not a limitation on 32 bit CPUs. And is therefore kind of irrelevant.

EDIT: Why am I even in this thread? I don't care about iMacs.
I made my point, which is that the limitation of RAM in any new mac has NOTHING to do with the CPU or OS, and everything to do with physical limitations, or memory controllers.
 
... A better alternative is to change HDD to Momentus XT. Own 4 gigabytes memory chip SSD, and thus the most frequently used programs are a very quick response. It will spoil you. I alone addressing the issue of how much RAM I need but I am discouraged price. It's amazing, and 4 gigabytes of RAM is enough for me. Super fast HDD is the solution.

Even I have also dealt with what processor for my demanding use is appropriate and now I know the dual core is enough only must have at least 2.5 GHz for multiple tasks(but 4 cores is 100% better). I've had personal problems with multiple high-definition Flash videos play and the most we helped change the wifi to wired and already mentioned HDD. And today I feel like a king and I am extremely happy with the responses of my laptop.

Have only mention the GPU, if you do not play the latest games is enough NVIDIA GeForce 320M for HD video.

Hope it can help somebody who wants have super fast NB for fair money :)
 
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