Hi

I'm looking for a used MBP and the only real requirement that I need is for it to house 4gb RAM.... I've seen/heard some 2.33ghz models can do this... but how do you tell which ones?

I'd hate to bid/buy one and then discovery it can't!! Is to do with when it was manufactured? (ie later ones can?)

Maybe I should only go 2.4+ to be safe!

Thanks

Ben

It's to do with the chipset used.

All Core 2 Duo MacBook Pros can be fitted with 4GB of RAM and will work fine.

However, the older Intel 945 chipset doesn't support memory remapping, whereas the newer 965 and nVidia 9400M do. The memory remapping is required to reassign some of the memory to an address space above that of the upper 32-bit address space that is reserved for the hardware devices . The upshot of this is that only 3GB of the 4GB fitted will be available to the operating system on a 945 based MacBook. The full 4GB will be available on the 965 and 9400M versions.

The transition point in the MacBook line was between the 2.16 & 2.33GHz models (945 chipset) to the 2.2 & 2.4GHz models (965 chipset).

Cool - thanks.

I ask because I'm watching a 2.33 on eBay which claimed to have 4gb RAM – I asked if this was just what was 'fitted' or what the system showed, and he posted a screenshot of the "About this Mac" actually registering the 4gb.

Is this okay then, or is it just stating the physical RAM fitted and not what the system will use?

It doesn't list the chips etc, so couldn't tell from that, but your info will show me what to look for on others!

The "about this Mac" dialogue just shows the installed RAM - not the amount available to the system.

The following screenshot is from my 945 chipset Mini with 4GB installed:



As you can see, it shows 4GB as the label for the pie chart, but if you add the Free memory (31.96MB) and the Used memory (2.96GB) together you can see that the total actually available to the system is only 3GB.

Great - thanks.... I'll stick to 2.4 and upward then!

I appreciate your help!

Sorry to keep asking..... would this be a full 4gb??

"Graphic details copy and pasted from the laptop for those who were intrested. GeForce 8600M GT: Chipset Model: GeForce 8600M GT Type: Display Bus: PCIe PCIe Lane Width: x16 VRAM (Total): 256 MB Vendor: NVIDIA (0x10de) Device ID: 0x0407 Revision ID: 0x00a1 ROM Revision: 3175 Displays: Color LCD: Display Type: LCD Resolution: 1680 x 1050 Depth: 32-bit Color Built-In: Yes Core Image: Hardware Accelerated Main Display: Yes Mirror: Off Online: Yes Quartz Extreme: Supported Display Connector: Status: No display connected"


I'm finding this pretty confusing! From your earlier info I guess some early 2.4's won't use all 4gb too... I spotted one on eBay with the '945' in the description....

The information you posted is for the graphics card not the main chipset. Apple being Apple don't make it very easy to tell what the chipset is - you can't get the info from the system profiler for example.

However, since Apple starting using the nVidia GeForce 8600M GT at the same time that they starting using the 965 chipset (and moved to 2.2 & 2.4GHz CPUs), I confirm that the MacBook Pro that information was pasted from will support the full 4GB.

Thank you...

I've managed to find today a 2.5ghz ex-display model from a Mac dealer for a pretty fantastic price – so thanks for your advice anyway – but this should be a little more 'future proof' (at least for the near future anyway!)

Cheers!

Ben