Apple does not seem too partisan when it comes to favouring either of today’s two makers of PC graphics processors, tending to oscillate between fitting either Nvidia or AMD’s graphics adaptors. Since the 15-inch MacBook Pro with Retina display was introduced in 2012, there has been a build using discrete Nvidia graphics in addition to low-power integrated Intel graphics, starting with the Nvidia GeForce GTX 650M for the Mark I; and for the last two refreshes, the slightly better GTX 750M.
Now we see the pendulum swing back to AMD, with the inclusion of a Radeon R9 M370X graphics processing unit. It is fitted with 2 GB of GDDR5 video memory, the same quota as the outgoing Nvidia part.
You won’t find this AMD graphics processor on other laptops though as the part seems to be custom-built for Apple. Note that like all GPUs that Apple has fitted to its professional-label MacBook Pro notebooks ever since the line was launched in 2006, the 2015 MacBook Pro takes a consumer-grade graphics adaptor, here bearing the Radeon name.
(Contrast this with professional workstation notebooks made by the likes of HP and Dell. Both AMD and Nvidia design graphics processors specially profiled for professional use, known as AMD FirePro and Nvidia Quadro respectively, built with more exacting standards for render accuracy and reliability. And possessing commensurately higher price tags too.)
The AMD Radeon R9 M370X looks to be based on a 28 nm architecture codenamed Cape Verde that dates back to 2012, and this particular version runs an 800 MHz GPU clock, 1125 MHz memory clock (4500 MHz effective speed, after the quadrupling properties of GDDR5 RAM) and 128-bit memory bus. It has 640 stream processors for parallel processing and 40 texture mapping units.
Comparing with Nvidia’s graphics is not straightforward as its architecture is slightly different, with a specification listing shading units (384) and render output processors (16) besides a count of 32 texture mapping units. However the previous Nvidia GTX 750M did have a slightly faster core-clock speed of 926 MHz, the same size 128-bit memory bus, and a faster memory clock of 1254 MHz (or 5016 MHz effective).
Apple reports that the new AMD graphics are faster than the outgoing Nvidia solution, and these claims were borne out in our testing in every instance, up to and including a 70 percent performance increase in one game.
Before the graphics benchmark results, it’s worth reiterating that the CPU is the same as when we last tested the breed in summer 2014. We ran the usual processor tests anyway as part of our comprehensive routine to ensure nothing unexpected had arisen, and found figures that were within 1 percent tolerance of last year’s results.
In brief, this means a single-core Geekbench 3 score of 3717 points, rising to 14,325 points in multi-core mode; Cinebench 11.5 with results of 1.54 and 6.41 points respectively for the two modes; while Cinebench 15 reported 132 and 602 points.
For reference, Dell’s comparable copycat computer is the Precision M3800 which runs an Intel Core i7-4712HQ at 2.3 GHz, and gives benchmark scores around 5 percent slower in Cinebench, and up to 18 percent slower in Geekbench.
Cinebench will also test graphics rendering performance with an OpenGL routine, and in our tests of the mid-2015 MacBook Pro with its new AMD graphics we found 12.5 and 16 percent improvements over the previous Nvidia model. Specifically, Cinebench 11.5 framerate rose from 48 to 54 fps, while Cinebench 15 advanced from 54 to 63 fps.
Turning to gaming, we started with Batman: Arkham City and found it would play around one-third faster. At the low setting of 1280 x 720 pixels and Medium detail, Nvidia gave us 61 fps while AMD played at 83 fps (36 percent faster).
Set to 1440 x 900 size – arguably the best resolution for this MacBook Pro’s 2880 x 1900-pixel display – the game rose from 50 fps through Nvidia GeForce GTX 750M, to 66 fps through the AMD Radeon R9 M370X, for a 32 percent improvement.
Unigine Heaven is a synthetic gaming benchmark, and here the AMD graphics showed around 20 percent improvements on the previous Nvidia – moving from 35 to 42 fps (1280 x 800, Medium), and from 29 to 35 fps (1440 x 900, Medium).
Most impressive gaming performance lifts were found in the 2013 reboot of the classic Tomb Raider game. In our experience testing Windows machines, this game typically works better through AMD graphics hardware – right down to the added TressFX™ graphics API for DirectX, which optionally shows Lara’s hair more realistically, each strand rendered separately with the help of the AMD Graphics Core Next architecture. Sadly this feature has not been ported to the OpenGL version of Tomb Raider for Mac.
Set to a modest 1280 x 800-pixel resolution and Normal detail, framerate was lifted from 40 fps under Nvidia to 65 fps under AMD (63 percent faster). At 1440 x 900, Normal detail moved from 33 to 56 fps (the vaunted 70-percent improvement) and from 31 to 49 fps at High detail (or a 58 percent lift).
With the help of QuickRes (www.quickresapp.com) we also pushed the graphics to their size limit, expanding screen resolution beyond what OS X normally allows, to the MacBook Pro’s native 2880 x 1800 pixels. At this point you cannot expect to have playable framerates from anything but the best graphics cards. For the Nvidia 750M, it averaged 9 frames per second in Tomb Raider, while the AMD R9 M370X showed us a much better, if still too slow, 18 fps. That’s what statisticians and marketeers would call a 100 percent improvement.
Both the new 15in MacBooks offer Intel Iris Pro Graphics, but the flag-ship model also boasts a discrete graphics card in the form of the AMD Radeon R9 M370X with 2GB of GDDR5 memory. The previous generation offered an Nvidia GeForce GT 750M instead.
Apple claims these new discrete graphics deliver up to 80 percent faster performance using new AMD Radeon R9 M370X graphics for editing video in Final Cut Pro X, rendering 3D images in pro graphics apps or playing high-resolution games.
To give you some idea of the difference offered by the discrete graphics card: Last year’s top model, with its Nvidia GeForce GTX 750M graphics, could average 56 fps when set to 1280 x 800 pixel resolution and Normal detail. Last year’s entry MacBook with Iris Pro graphics played the same test at 59 fps, and could still sustain a 46 fps average after moving up to High detail. That’s with the game set to use legacy OpenGL. (Read our review the 2014 2.2GHz 15in MacBook Pro here).
2015 MacBook Pro 15in review: Display
The 15in MacBook Pro has a Retina display that offers a resolution of 2,880 x 1,800 pixels.
When we tested the Retina display in the 2014 MacBook Pro with Retina display we found this panel to have 96 percent coverage of the sRGB colour gamut, and 80 percent of the more challenging Adobe RGB gamut. Contrast ratio was 680:1 when set to 50 percent brightness, 720:1 at 75 percent, and 810:1 at full brightness.
It’s unlikely that this will have changed, unless Apple is using a different supplier for the screen – on last year’s model it was a Samsung LCD, but we have seen LG/Philips displays used for some models of the MacBook Pro with Retina display. We are hopeful because when we tested the 2.7GHz 13in model we found some indication that the screen had been tweaked. Last time we measured the 13-inch Retina display of the MacBook Pro in June 2014, it had 91 percent coverage of sRGB, and 68 percent Adobe RGB. With the new model, figures have improved, to 97 and 73 percent respectively. We are in anticipation of a similar improvement with the 15in models.