Apple's iPad 3, Part 1: The Complete Retina Display And A5X Review

CPU And GPU Performance: All About Graphics

The CPU: A9 Flavour

The iPad 3 features a new SoC, the A5X. Like the preceding A5, it features a dual-core A9 ARM processor clocked at 1 GHz. We've covered the architecture of the A9 in the past, so we won't revisit the details, but for those interested in a deeper discussion, you can head back to our original A5 coverage.

Apple A4 (iPad)
Apple A5 (iPad 2)
Apple A5X
Fab Node
45 nm
45 nm
45 nm
1 GHz ARM Cortex-A8 (single-core)
1 GHz ARM Cortex-A9 (dual-core)
512 MB LP-DDR2
PowerVR SGX535 (single-core)PowerVR SGX545MP2 (dual-core)PowerVR SGX545MP4 (quad-core)
L1 Cache
32 KB / 32 KB
32 KB / 32 KB
L2 Cache640 KB
1 MB

On paper, there's really nothing to suggest improved CPU performance from the A5X. There's no change in cache size, and though there's apparently twice as much on-die RAM, it has no impact on raw computational horsepower. The new A5X seems intended to help improve multitasking support and enable a beefier graphics engine, so our GeekBench results are, not surprisingly, largely unchanged.

GeekBench v2.2.7 Results
iPad 2
iPad 3
Dell Mini 1012
LePan II
Transformer Prime
Apple A5
Apple A5X
Atom N450
Tegra 3
Dual-core A9
Dual-core A9
Single-Core Atom
Dual-core ScorpionQuad-core A9
1 GHz1 GHz1.66 GHz1.2 GHz1.4 GHz
Floating Point

The GPU: Double Your Pleasure

One aspect of Apple's A5X truly shines: graphics performance. Since an ultra-high-resolution display is the iPad 3’s core selling point, Apple's A5X features a significantly more powerful graphics engine optimized for the Retina display. This increases gaming potential by a lot. In fact, Apple claims the iPad 3 offers double the graphics performance of the iPad 2. How is this possible?

GPU System-on-Chip
PowerVR SGX 535
(Apple A4)
PowerVR SGX 543
(Apple A5/A5X)
Bus Width (in bits)
Triangle rate @ 200 MHz
14 MTriangles/s35 MTriangles/s

Apple still employs Imagination's PowerVR SGX543 architecture, used in the iPad 2. But whereas the iPad 2 was limited to a dual-core implementation (SGX543MP2), the iPad 3’s A5X sports a muscular quad-core GPU (SGX543MP4). Incidentally, Sony's PlayStation Vita also uses the SGX543MP4.

That hardware change is easy to spot when you inspect the A5X's die. In the annotated layout above, you can quite clearly identify each of the four GPU cores. It also appears that RAM accesses has changed to accommodate the increased need for bandwidth. The A5 employed a pair of memory interfaces; UBM's image above suggests four on the A5X. To get a more illustrative story, though, let's look at GLBenchmark.

GLBenchmark 2.1.2
*native resolution
iPad 2
iPad 3
Kindle Fire
LePan II
Transformer Prime
PowerVR SGX543MP2
PowerVR SGX543MP4PowerVR
Adreno 220
Tegra 3 (ULP GeForce)
Egypt Standard*
6661 frames (59 FPS)
6709 frames (59 FPS)
2847 frames (25 FPS)
3485 frames (31 FPS)
5388 frames (48 FPS)
Egypt Fixed Time Step*
47.598 s (59 FPS)
47.261 s (60 FPS)
116.138 s
112.659 s (25 FPS)
69.055 s (41 FPS)
Egypt Off Screen (720p)
10 146 frames (90 FPS)
15 663 frames (139 FPS)
2516 frames (22 FPS)
3603 frames (32 FPS)
6496 (58 FPS)
Pro Standard*
2962 frames (59 FPS)
2975 frames (60 FPS)
1981 frames (39 FPS)
2140 frames (43 FPS)
2726 frames (54 FPS)
Pro Fixed Time Step*
20.868 s (60 FPS)
20.857 s (60 FPS)
34.658 s
31.982 s (39 FPS)
24.189 s (52 FPS)
Pro Off Screen (720p)
7352 frames (147 FPS)
12546 frames (251 FPS)
2277 frames (46 FPS)
2332 frames (47 FPS)
3717 frames (74 FPS)

According to the standard tests in GLBenchmark, nearly identical scores on the iPad 2 and iPad 3 imply similar perceived overall gaming performance. That doesn't seem like it'd blow you away, but it's actually pretty amazing when you consider the iPad 3's 2048x1536 native resolution. Comparing these two devices at their native resolutions is by no means an apples-to-apples match-up. But it is cool that the iPad 3’s A5X delivers the same performance with four GPU cores at 2048x1536 resolution as the iPad 2’s A5 with two cores at 1024x768.

Comparing the raw graphics performance of each hardware implementation using GLBenchmark's off-screen tests reveals that the A5X delivers about 1.5-2x more performance than the A5. More interestingly, the Tegra 3-based Transformer Prime actually falls behind the older iPad 2. In fact, when we compare the Transformer Prime to the iPad 3, we see a two- to three-fold jump in performance favouring Apple's tablet.

GLBenchmark 2.1.2
iPad 2
iPad 3
Triangle Test
65.0 Mtriangles/sec
129.2 Mtriangles/sec
Triangle Texture Test
58.0 Mtriangles/sec
120.8 Mtriangles/sec
Triangle Texture Test, Vertex Lit
45.6 Mtriangles/sec
93.6 Mtriangles/sec
Triangle Texture Test, Fragment Lit
43.5 triangles/sec
92.3 Mtriangles/sec

According to Imagination, its PowerVR tile-based deferred rendering architecture is highly dependent on memory bandwidth, which means there's a direct relationship between throughput and triangle rates. Based on our results from the iPad 3, it's pretty clear that graphics performance improvements are related both to a more complex GPU and greater bandwidth. The iPad 2 and iPad 3 seemingly both employ 1066 MT/s LP-DDR2 by way of a dual-channel configuration. However, the iPad 3 utilizes four 32-bit memory interfaces, which is two more than its predecessor.

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  • theconsolegamer
    Gaming in a 2500x1440 panel @ 1280x720 resolution..... Genius!

    Watching movies in a 2500x1440 panel @ 1920x1080..... Revolutionary!

    Bragging about a 2500x1440 panel that won't be really used..... Priceless!
  • mi1ez
    Got to have the hardware before the software makers will design for it. Also, hopefully this will push Android and W8 tablets to push up their resolutions. Maybe even desktop monitors!
  • testerguy
    theconsolegamerHaving the choice to game in a 2048x1536 panel @ 1024x768 resolution..... with 4x the FPS of the fastest equivalent Android tablet. Genius! As well as having the ability to game at the highest resolution on any tablet ever created.

    Watching movies in a 2048x1536 panel @ 1920x1080..... necessary if you want to have the appropriate format for portrait use which is the majority of the time. !

    Bragging about a 2048x1536 panel that won't be really used..... except for everything including web browsing, photo editing, emails, recording videos, gaming, and every single app which comes out which is designed specifically for that resolution, Priceless!
  • techpops
    Brilliant article. Finally I get some real details. After spending so much on a PC upgrade recently, I'm not in a position to spend on an ipad3 but eventually I'll get around to it if there isn't a suitable alternative by then with equally high resolution.

    What I'd like to know, not having owned an ios device before is how satisfying is it to use an ipad3 as a device for managing and reading all your comics, technical manuals, magazines and books in a variety of different formats. All my magazine are in PDF format but books are mostly mobi, comics in a variety of formats. How well does ipad support all these formats?

    Really for many years now I've wanted a tablet like device that would allow me to read my huge collections of comics and PDF's in a resolution high enough to do them justice. This is the first device that seems to fit that dream spec at least in terms of hardware but just how much fun is it living in the Apple universe managing all your content? Under Windows I have such a great time accessing anything with the written word in it . With Directory Opus I've been able to create libraries of my stuff that's instantly searchable, looks beautiful with huge thumbnails of everything and is all arranged in sensible hierarchies of folders so I can jump straight to main categories of stuff I want. How does ipad compare here and if it's lacking with file management, is that something that can get better once you jail break the device?

    Finally I'm really curious how well ipad handles accessing data beyond the memory of what's built into the ipad itself. My comics collection is 50gb alone so it's not like I'd be able to copy everything onto the ipad locally. Can it deal with stuff on a network? I'd be buying into the cheaper lower memory ipad as the premium on the higher memory models seems absurd. I'd much rather use cheap memory cards and usb sticks for storage.