Which GPU for Photoshop CC?

[SVTmaniac]

I have a late 2013 15" rMBP with the 750M. I'm using gfxCardStatus to switch between the Iris Pro and the 750M, but I'm confused as to which one actually performs better in Photoshop CC.

I've read the the Iris pro is much better at OpenCL than the 750M and under the Performance tab of Photoshop it has a "Use OpenCL" checkbox that is checked. So does that mean the Iris Pro would give me better results in Photoshop than the 750M?

 

[yjchua95]

I have a late 2013 15" rMBP with the 750M. I'm using gfxCardStatus to switch between the Iris Pro and the 750M, but I'm confused as to which one actually performs better in Photoshop CC.

I've read the the Iris pro is much better at OpenCL than the 750M and under the Performance tab of Photoshop it has a "Use OpenCL" checkbox that is checked. So does that mean the Iris Pro would give me better results in Photoshop than the 750M?

You got that right.

With that checkbox checked, I find that Iris Pro performs faster than the 750M in my 15" rMBP in PS-CC.

 

[SVTmaniac]

You got that right.

With that checkbox checked, I find that Iris Pro performs faster than the 750M in my 15" rMBP in PS-CC.

Cool, that works since I'll get better battery life as well.

 

[SVTmaniac]

Ok so one downside I've just encountered. I can't use the Iris Pro while connected to my TB display. It must use the 750M when connected to an external display. This sucks because I do most of my Photoshop work while connected to the TB display. Wonder if this is a hardware or software limitation?

 

[thekev]

Ok so one downside I've just encountered. I can't use the Iris Pro while connected to my TB display. It must use the 750M when connected to an external display. This sucks because I do most of my Photoshop work while connected to the TB display. Wonder if this is a hardware or software limitation?

It is an issue of hardware. The machines with integrated graphics only can still use the thunderbolt display, but it's not physically possible to use integrated graphics with an external display on your machine. For photoshop you shouldn't have any performance issues related to either of those gpus. This issue is just so over-hyped. Also when you have an external display handy, you obviously have access to a power outlet. The battery thing should be a non-issue there.

 

[SVTmaniac]

It is an issue of hardware. The machines with integrated graphics only can still use the thunderbolt display, but it's not physically possible to use integrated graphics with an external display on your machine. For photoshop you shouldn't have any performance issues related to either of those gpus. This issue is just so over-hyped. Also when you have an external display handy, you obviously have access to a power outlet. The battery thing should be a non-issue there.

Good to know, I figured the 750M was plenty powerful, but of course if the Iris Pro is faster I wanted to use it. When I use my TB display it is connected to power so there is no worry about battery life. I'm more thinking of when I'm on the go. I travel a lot with my photography so I do a lot of editing on the plane and in the terminal. I don't always have access to an outlet.

 

[thekev]

Good to know, I figured the 750M was plenty powerful, but of course if the Iris Pro is faster I wanted to use it. When I use my TB display it is connected to power so there is no worry about battery life. I'm more thinking of when I'm on the go. I travel a lot with my photography so I do a lot of editing on the plane and in the terminal. I don't always have access to an outlet.

I don't think you'll have much in the way of performance complaints. There are a couple newer filters that are optimized specifically with gpu use in mind. The others used to run on the cpu. They may have taken a few seconds on the cpu. On the gpu their rendering is nearly instant assuming all data is contained in memory. The difference between one and another won't make a big difference there, as it's not really the same as something like a brush where you really need that real time feedback to work comfortably. In this case I don't think a couple tenths of a second will make much difference. In the case of applying multiple adjustments to a large number of images, most people do that in lightroom, so there still isn't any real difference. I say that because lightroom doesn't touch the gpu or OpenCL libraries.