[snoopy199]

The apple site is a little confusing.
First there's the macbook specifications page stating that it has 64meg and with the footnote it states 80 meg minimum
Macbook Specs

But aKB Article contradicts this. It says
"The GMA950 allocates a base amount of 80 MB for video and boot processes at startup. In a MacBook configured with 512 MB of SDRAM, this leaves 432 MB of SDRAM available to Mac OS X.
Mac OS X may make additional main memory available to the graphics processor for texture use beyond the base 80 MB amount mentioned above, depending on the application being used."

It seems confusing that Apple advertises the card as a 64meg GPU but buried in the KB library a document stating that it can access/use more memory

Any wisdom on this issue would be very helpful

[Sage]

Just a guess: overhead?

[snoopy199]

I'm not asking the difference between 80 and 64 but rather how much total can the GMA950 use under OSX? It appears that the card can and does use more then the 80 meg.

-D

[TheoCryst]

Supposedly GMA950 should use 80 megs (64 VRAM + 16 overhead) by default. However, when you are running a particularly graphics-intensive application (read: games) the chipset can dynamically allocate itself additional memory, up to 224 megs.

[snoopy199]

Originally Posted by TheoCryst

Supposedly GMA950 should use 80 megs (64 VRAM + 16 overhead) by default. However, when you are running a particularly graphics-intensive application (read: games) the chipset can dynamically allocate itself additional memory, up to 224 megs.

Thanks,

I've been seeing reports and seeing posts around the net stating that its a 64meg card no more no less (plus the 16 meg for overhead). The specifications on apple.com also seem to indicate that fact and people have assumed that apple has capped the memory usage of the card under osx. In contrast is the wording about 80 meg minimum on the foot note of the specs page. Then there's the KB article that seems to inidicate that apple did not cap memory.

[Dork.]

Originally Posted by darth-vader000

Thanks,

I've been seeing reports and seeing posts around the net stating that its a 64meg card no more no less (plus the 16 meg for overhead). The specifications on apple.com also seem to indicate that fact and people have assumed that apple has capped the memory usage of the card under osx. In contrast is the wording about 80 meg minimum on the foot note of the specs page. Then there's the KB article that seems to inidicate that apple did not cap memory.

I'm reasonably sure that when the Intel Mac Mini with the GMA950 first came out, its specifications said that the memory card used 64 MB + 16 MB "maximum", not "minimum" as it says now. That's the source of all the info you're seeing on the net. You're correct in that all the information you can find coming out of Apple now states that there is no such limit. I think there are two possible explanations for this:

- They simply put the wrong text down on the Mac Mini Specs page and it could always use more memory, and now the Internet won't forget about it. The card probably is limited to 64 MB when there's the stock 512MB installed, but can go higher if more system memory is available.

- The limit really did exist at first (inside OS X), since OS X is such a memory pig that Apple wanted as much memory available to the system in all configurations, and figured 64 MB ought to be enough for everyone. But then BootCamp came out, and when Intel Macs with the GMA950 booted into XP, they did not have this limit. They also performed better while running games, and Apple removed the limit to try and close that gap.

[Eug Wanker]

My MacBook says the GPU gets only 64 MB (not counting overhead), even though I have 2 GB RAM installed.

Under Windows it's 224 MB.

I'm still not 100% sure if OS X is capped at 64 MB, or perhaps there are specific circumstances OS X will release extra RAM? I tend to believe the form and not the latter though. I tried a simple Exposé test on Intel Mac mini which seems to suggest that a 1 GB machine is still capped at 64 MB. After 9 big open Safari windows, Exposé started to lag. I suspect it wouldn't if the GPU had 128 MB.

[powerbook867]

If Windows can see 224mb, then I wonder if through an app or a script we could dynamilcally reconfig the memory allocation? I wonder if it would increase performance?

[Socially Awkward Solo]

Originally Posted by powerbook867

If Windows can see 224mb, then I wonder if through an app or a script we could dynamilcally reconfig the memory allocation? I wonder if it would increase performance?

Apple said in OSX it gets about 64 megs but using a 3D heavy app it can take more but they didn't say how much.

[Eug Wanker]

Originally Posted by powerbook867

If Windows can see 224mb, then I wonder if through an app or a script we could dynamilcally reconfig the memory allocation? I wonder if it would increase performance?

Probably not for games, because 64 MB is usually enough for the rez in practical terms. If you start increasing things too much the GPU isn't fast enough anyway, so the GPU becomes more of a limitation than the memory I'd guess. There's not much point in having it 20% faster if it is still unplayable. ie. 12 fps vs 10 fps is still useless.

However, I wonder how much it would help on something like Exposé when you add an external screen. IIRC, Exposé per se doesn't use a ton of raw GPU power. It's more dependent on memory bandwidth. Exposé eats up video memory fast when you start opening lots of application windows, and once you hit the limit, it starts to stutter.

OTOH, GMA 950 is already using system RAM anyway, so I wonder how much the performance will change.

[wilsonng]

We can only imagine it that the GMA 950's RAM requirements would double if ithe MB had to do dual monitors.

Has anyone seen the amount of free memory drop when connecting the MB to an external?

[powerbook867]

Eug, that was exactly what I was thinking when I mentioned controlling the amount of ram allocated to video...I need to pick up a mini-dvi to dvi cable and hook my 20 inch cinema display up sometime soon and I wonder what kind of performance boost would be seen in day to day use....

wilsonnq, that's a good idea..