discrete graphics vs. battery life?

[andrewwg94]

i'm shopping for a new 15" MBP. I know I want 2.5 Ghz, 512 gb SSD so without discrete graphics it's $2400 and with its $2500. I don't think I need discrete graphics but a $100 more is not a big difference. I care more about battery life. Is the battery life better with integrated graphics? I know 'officially' it's the same, but realistically?

I'm a software developer and I'm into photography so I use Lightroom. I don't play video games on my computer and I don't edit video. Is there any use for me for the AMD graphics?

 

[mcarling]

Yes, you'll have somewhat better battery life and probably better reliability without the discrete GPU. I ordered my 2.8GHz mid-2015 MBP without the discrete GPU and I'm glad I did.

 

[andrewwg94]

Yes, you'll have somewhat better battery life and probably better reliability without the discrete GPU. I ordered my 2.8GHz mid-2015 MBP without the discrete GPU and I'm glad I did.

what do you mean by reliability?

 

[mcarling]

what do you mean by reliability?

Past MBPs have had a history of reliability problems with discrete GPUs. The discrete GPUs seem to be the most failure-prone component in MBPs.

 

[leman]

I don't think that anyone can give you the answer you are looking for, because there is simply no empirical data on the matter. It is possible that the dGPU will reduce your battery life, but it is also possible that it will prolong it — depending how you think about it. One would really need to measure these things to be sure.

I think, for your usage, you don't really need a dGPU. But it could also speed up some operations in Lightroom (no idea if it uses OpenCL yet).

 

[pendragon1984]

It's important to know that using gfxcardstatus you can turn off the discrete GPU whenever you want. For 100 extra I'd just get it. You can leave it turned off all the time. There might be a day when you will be happy you have it. It's over twice as fast as the integrated GPU.

I have the rMBP with the 750m. Using the integrated graphics I get about an extra 45 minutes to 1 hour of battery. But most of the time, recently, I haven't needed the extra battery life. So, I just use the 750m. Everything is a little smoother using the 750m, especially when pushing the computer. Also, as the 750m has it's on memory, I end up with more RAM available.

 

[ohbrilliance]

Lightroom takes advantage of the GPU, whether integrated or not. According to this document, it only speeds up operations in the developer module: https://helpx.adobe.com/lightroom/kb/lightroom-gpu-faq.html

I just ran a test on exporting 30 images (exporting being the function that is most time-consuming for me), and it made no difference whether the "Use Graphics Processor" LR option was enabled or not. You'd probably want to research further on the benefits of a dGPU in LR, if that was important to you.