Snow Leopard Allow 8 Gig?

[Cave Man]

It was either iFixit or maybe XLR8 that tried it when it first came out -- same problems as the slightly older MBPs -- 8 GB was recognized, but the system slowed down dramatically when > 4 GB were addressed.

I have a hypothesis that I'd love to test if I could get my hands on a SR MacBook. I suspect that OS X sees 8 gb of RAM and 256 (or 512) mb of vRAM on a MBP and sums them. This breaks the 8 gb barrier and leads to the poor performance. Windows doesn't do this because the vRAM is automatically subtracted from available RAM (i.e., memory penalty). If I could find a SR MB I'd put my two 4 gb sticks in it to test my hypothesis. But alas, I know no one who has one.

 

[ninjapenguinart]

My hypothesis for the reason why the 15 in does not have the ability to have 8gb of ram is not because of hardware, because the 17 and 15 have the same hardware, except for 2 things:

Battery
Screen
Processor Speed

So, my hypothesis is that Apple wanted people to have high battery performances in their 15in by keeping their memory low. So they edited the EFI to limit the usable memory.

 

[Cave Man]

But that doesn't explain the limitation on the Santa Rosa MacBook Pros.