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starstreak

macrumors 6502
Original poster
Dec 5, 2004
456
12
How does macbook choose which GPU to use Intel 4000 and nvidia chips? When something demands faster GPU, it somehow switches GPU? Or do I have to tell it which GPU I want to use before I boot up or something?

And does the MBPR come with any indicator that shows when the unit is in sleep mode or something?
 
Looks like it doesn't support the Ivy Bridge/Nvidia setup yet (i.e. Intel 4000/GT650).
 
GPU switching is initiated by calling OpenGL

Not quite.

I think it is one of the other libraries. When i open twitter it wants discrete GPU on my MBP 2011.

The in-built GPU switching is retarded. As soon as gfxcardstatus works on the new machines, I would recommend it.

I run it and force integrated when on battery and auto-switch when on AC.

Otherwise you end up running one little innocuous app that has an animation in its UI or something and your battery life is halved for no gain in performance....
 
oh yes, apps and webpages alike call OpenGL to render their UI and/or contents

What? No they don't...basic UI is rendered by Quartz.

The switching process is a lot more complicated than "if application "A" makes an OpenGL call, switch to dedicated GPU"
 
Gfxcardstatus still works in a very basic mode. You have the option of clicking switch cards, it just won't tell you which one is being used. You can use About This Mac to see which one is active.
 
oh yes, apps and webpages alike call OpenGL to render their UI and/or contents

Yeah, I read arstechnica too (do you?).

arstechnica said:
Apps that use advanced graphics frameworks such as OpenGL, Core Graphics, Quartz Composer or others will cause the OS to trigger the discrete GPU.

openGL is ONE OF the things that will make it switch, but not the ONLY thing.

I'm pretty sure it is actually core animation that makes it switch in twitter's case.

Either way, it isn't as straightforward as "don't run 3d apps" to stay on integrated GPU.

Apple really need to work on the GPU switching (maybe somehow make it application accessible via some sort of "do you want discrete GPU" flag that the developer can set to OFF if HD3000/4000 is enough), at the moment it is totally useless for saving battery life as a whole heap of apps make it switch (because they use say, core animation) that get pretty much zero benefit from the discrete GPU.

Off the top of my head:
- twitter
- soundcloud
- VMware Fusion (even if i don't want accelerated 3d)
- Flash
- VLC


ALL of those apps run just fine on an MBA with no discrete gpu to switch to. When they force a GPU switch, my battery life goes down the toilet, by at least a couple of hours (unless i force integrated with gfxcardstatus)... heat and fan noise also go up.


At the end of the day my point still stands: the auto graphics switching is crap, and will drain your battery far more than necessary.


Its one of only 2 gripes I have with my 2011 MBP:
- gpu switching
- fan noise under load
 
Last edited:
Yeah, I read arstechnica too (do you?).



openGL is ONE OF the things that will make it switch, but not the ONLY thing.

I'm pretty sure it is actually core animation that makes it switch in twitter's case.

Either way, it isn't as straightforward as "don't run 3d apps" to stay on integrated GPU.

Apple really need to work on the GPU switching (maybe somehow make it application accessible via some sort of "do you want discrete GPU" flag that the developer can set to OFF if HD3000/4000 is enough), at the moment it is totally useless for saving battery life as a whole heap of apps make it switch (because they use say, core animation) that get pretty much zero benefit from the discrete GPU.

Off the top of my head:
- twitter
- soundcloud
- VMware Fusion (even if i don't want accelerated 3d)
- Flash
- VLC


ALL of those apps run just fine on an MBA with no discrete gpu to switch to. When they force a GPU switch, my battery life goes down the toilet, by at least a couple of hours (unless i force integrated with gfxcardstatus)... heat and fan noise also go up.


At the end of the day my point still stands: the auto graphics switching is crap, and will drain your battery far more than necessary.


Its one of only 2 gripes I have with my 2011 MBP:
- gpu switching
- fan noise under load

When Apple first introduced the graphics switching, they promised a user configurable "white list" where you could add apps that wouldn't auto-swap. Looks like that feature never made it...
 
When Apple first introduced the graphics switching, they promised a user configurable "white list" where you could add apps that wouldn't auto-swap. Looks like that feature never made it...

Would be nice. I still think a exposing a "I want discrete GPU!" flag to application developers would be a better idea though. The user shouldn't have to worry about this crap. The app developer is in a better position to know whether or not their app can make good use of a discrete GPU.


if any of your running apps set the "i want 3d" flag, the card switches...
 
Not quite.

I think it is one of the other libraries. When i open twitter it wants discrete GPU on my MBP 2011.

The in-built GPU switching is retarded. As soon as gfxcardstatus works on the new machines, I would recommend it.

I run it and force integrated when on battery and auto-switch when on AC.

Otherwise you end up running one little innocuous app that has an animation in its UI or something and your battery life is halved for no gain in performance....

Have you seen some type of lagging with the Intel 3000? I'm planning on install this gfxcardstatus on my 2011 MBP. It will definitely help me on school days with the battery life. At school will work only on things like safari, office and just common everyday use apps. What do you think?
 
Have you seen some type of lagging with the Intel 3000? I'm planning on install this gfxcardstatus on my 2011 MBP. It will definitely help me on school days with the battery life. At school will work only on things like safari, office and just common everyday use apps. What do you think?

Its perfectly usable - don't forget the MBAs only have HD3000 - so for basic stuff it is more than capable of keeping up.

I have a hires 2011 (1680x1050) - you sometimes notice a very slight stutter (which might not even be gpu related) when swiping between desktops but it is by no means bad. Certainly not worth giving up 2+ hours of battery life over.

I'd definitely suggest downloading gfxcardstatus and setting it to run integrated GPU only when on battery.

When you're running something that really needs 3d horsepower, battery doesn't last very long anyway (eta from say 80-90% to zero was 45 minutes when I tried it running Neverwinter Nights 2 :D), so you're usually plugged into AC when doing that anyway I find.

The battery life gain you'll get is very significant.
 
Its perfectly usable - don't forget the MBAs only have HD3000 - so for basic stuff it is more than capable of keeping up.

I have a hires 2011 (1680x1050) - you sometimes notice a very slight stutter (which might not even be gpu related) when swiping between desktops but it is by no means bad. Certainly not worth giving up 2+ hours of battery life over.

I'd definitely suggest downloading gfxcardstatus and setting it to run integrated GPU only when on battery.

When you're running something that really needs 3d horsepower, battery doesn't last very long anyway (eta from say 80-90% to zero was 45 minutes when I tried it running Neverwinter Nights 2 :D), so you're usually plugged into AC when doing that anyway I find.

The battery life gain you'll get is very significant.

Thanks a lot! gfxcardstatus downloaded and running!
 
Looks like it doesn't support the Ivy Bridge/Nvidia setup yet (i.e. Intel 4000/GT650).

There is an updated version coming out today with full 2012 MBP support. If you follow the programmer on Twitter he has already provided the beta. I am running it now and can verify that it works 100%.
 
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