Mobile Intel 945GM Express Chipset - What's the max RAM

[coolVariable]

Am having a discussion what the max amount of RAM for that chipset is ...
Google did not help and the intel website does not say.
This is the chipset in a Lenovo x60t with a Core 2 Duo.

Is it 4GB or 3GB?

 

[Pabster]

It is 4GB.

 

[coolVariable]

Originally posted by: Pabster
It is 4GB.

Any links?

 

[Pabster]

Originally posted by: coolVariable
Any links?

Check the list.

 

[coolVariable]

Question: With a 32bit OS, the OS will only be able to use 4GB less the amount of video memory and the address space for periphals et al.

What if the video chip uses shared memory?

Does that mean you loose 2x the amount of shared memory?

E.g. If 128MB is shared with video, does that mean the available RAM to the OS is:
4GB - 128MB (address space for video memory) - 128MB shared memory =
RAM - address space other devices =
available RAM to 32 bit OS

 

[coolVariable]

Anyone?

 

[Ruptga]

Originally posted by: coolVariable
Question: With a 32bit OS, the OS will only be able to use 4GB less the amount of video memory and the address space for periphals et al.

What if the video chip uses shared memory?

Does that mean you loose 2x the amount of shared memory?

E.g. If 128MB is shared with video, does that mean the available RAM to the OS is:
4GB - 128MB (address space for video memory) - 128MB shared memory =
RAM - address space other devices =
available RAM to 32 bit OS

I'm pretty sure you'd only lose the 1x the address space, since it's effectively moved from system memory to video memory, not mirrored

 

[coolVariable]

You sure?

 

[Blain]

 

[coolVariable]

Mmmmhhh, despite long searches with Google, I was unable to find any definitive answer.

Anyone on AT that tried this?


I would also be curious to know more about that PAE switch for 32bit Vista and XP.
Apparently it tricks the OS to see more than 4GB ... but it is dependent on the CPU?

 

[Peter]

/PAE actually uses 36-bit addressing only with "server" grade microsoft OS. All others use PAE mode for the sole purpose of getting to the "no-execute" attribute for enhanced virus protection.

And of course you'll need a CPU that actually has a 36-bit address bus. For Intel mobile processors, that means you need a core-2. Core won't do.

 

[coolVariable]

I can't find anything definitive but I believe Vista and XP are capable of this too.

I ordered a system with a Core 2 Duo

 

[hans007]

i think there is actually a limit to 3gb on the 945gm.

i dont remember the actual reason why, but its the reason why you cant get a macbook with 4gb, it only sees 3.25 gigs for some reason