Upgrading ram on my Macbook Pro

dantonkin

dantonkin

dantonkin

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Hi there,

I've been doing a bit of Googling as to whether my Macbook Pro will support 4gb ram. However, I've had no luck finding any info.

It was bought about a year ago, if that helps, and is the 2ghz Intel core duo model.

Any help would be much appreciated.
 
Dantonkin, I swear my MBP manual tells me the max my Pro can support? In the upgrading memory bit... but as with Dr Jones, I could be wrong also :)

Excuse my ignorance, but if you try to install 4GB+ in Windows Vista/XP x86 it will not recognise the full 4GB, you only see 3.5GB or sumin similar.

But how comes OS X can recognise up to 16GB (prob more, but Im going by what the Mac Pro can support) when OS X is a 32bit operating system? I thought the limitation of 4GB+ RAM was a 32bit issue? Just curious to know how it works?
 
IRT the original post, I think a MBP that old only supports 3GB RAM. iirc its not an OS thing its a hardware thing.

I dont know all the details about the Windows RAM thing but as far as I know its a bug.

OS X (Tiger onwards) is a 64bit operating system. So that answers your question. :)
 
keogh said:
Dantonkin, I swear my MBP manual tells me the max my Pro can support? In the upgrading memory bit... but as with Dr Jones, I could be wrong also :)

Excuse my ignorance, but if you try to install 4GB+ in Windows Vista/XP x86 it will not recognise the full 4GB, you only see 3.5GB or sumin similar.

But how comes OS X can recognise up to 16GB (prob more, but Im going by what the Mac Pro can support) when OS X is a 32bit operating system? I thought the limitation of 4GB+ RAM was a 32bit issue? Just curious to know how it works?
Click to expand...

It's a hardware thing.

The 32 bit Intel processors that are in the older MacBook Pros can only support 3GBs of RAM. The new Santa Rosa processors are 64 bit and can support 4GBs of RAM.

So the maximum your MacBook Pro can take is 3GBs using 1x1GB and 1x2GB or 2x2GB.
 
In a nutshell:

Core Duo = 32bit
Core 2 Duo = 64bit

In theory a 32bit system can handle 4GB but in practise other devices hog the address space. Obviously that limitation is obliterated by 64bit addressing.
 
keogh said:
Dantonkin, I swear my MBP manual tells me the max my Pro can support? In the upgrading memory bit... but as with Dr Jones, I could be wrong also :)

Excuse my ignorance, but if you try to install 4GB+ in Windows Vista/XP x86 it will not recognise the full 4GB, you only see 3.5GB or sumin similar.

But how comes OS X can recognise up to 16GB (prob more, but Im going by what the Mac Pro can support) when OS X is a 32bit operating system? I thought the limitation of 4GB+ RAM was a 32bit issue? Just curious to know how it works?
Click to expand...

You are right, it does say in the manual! Turns out my Macbook Pro can only accept 2gb max using 2x pc2-5300 ddr2 667mhz ram.

That sucks, I wanted to get 3 gigs min in there, along with a new 7200rpm hdd and Leopard!

:mad:
 
dantonkin said:
You are right, it does say in the manual! Turns out my Macbook Pro can only accept 2gb max using 2x pc2-5300 ddr2 667mhz ram.

That sucks, I wanted to get 3 gigs min in there, along with a new 7200rpm hdd and Leopard!

:mad:
Click to expand...
The chipset supports 4Gb, unsure if Apple use EFI or whatever to limit to 2Gb or if it's a "we've not tested it with more" limit. Stick 4Gb in and you'll not be able to use all of it as devices like the graphics RAM use the address space, hence why the pre-santa rosa Core2 machines are limited to 3Gb.
 
I have a new 2.4ghz MacBook Pro, it already has 2gb and can take 4gb.
Do I need to replace all the ram with some OCUK stuff? Or can I just buy a 2gb kit and add it with no drop in performance?

Thanks in advance
 
griffy said:
I have a new 2.4ghz MacBook Pro, it already has 2gb and can take 4gb.
Do I need to replace all the ram with some OCUK stuff? Or can I just buy a 2gb kit and add it with no drop in performance?

Thanks in advance
Click to expand...
The sticks that come in it as standard are 2x1GB and it only has two slots so you don't add memory to it to make 4GB, you replace what's already there.
 
It'll have 2x1Gb sticks from the factory, so you need to remove all the factory RAM to upgrade to 4Gb. 2Gb sticks of RAM are 4x the price of 1Gb sticks at the moment so it's poor value. Looking at £170+ for 4Gb, you'll get £30 back for the old RAM if you're lucky.
 
MagicBoy said:
The chipset supports 4Gb, unsure if Apple use EFI or whatever to limit to 2Gb or if it's a "we've not tested it with more" limit. Stick 4Gb in and you'll not be able to use all of it as devices like the graphics RAM use the address space, hence why the pre-santa rosa Core2 machines are limited to 3Gb.
Click to expand...

May just try a 2gb stick then.
 
MagicBoy said:
The chipset supports 4Gb, unsure if Apple use EFI or whatever to limit to 2Gb or if it's a "we've not tested it with more" limit. Stick 4Gb in and you'll not be able to use all of it as devices like the graphics RAM use the address space, hence why the pre-santa rosa Core2 machines are limited to 3Gb.
Click to expand...
It's an Intel chipset limitation.
 
EVH said:
It's an Intel chipset limitation.
Click to expand...

That's why I said "The chipset supports 4Gb".

http://www.intel.com/products/chipsets/945pm/index.htm


So why do apple say 2Gb max on a Core Duo MBP?

I can only think they've limited it using another method, as the IBM T60s at work with the same chipset and CPU will see 4Gb (with the 3.3Gb useable problem). I'm quite happy to test some 2Gb SODIMMS in my MBP is anyone wants to offer ;)
 
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