Apple iPad 2 GPU Performance Explored: PowerVR SGX543MP2 Benchmarked

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• Azethoth - Saturday, March 12, 2011 - link

  I think you misspelled "will scale poorly". The worst would be battery life if all 4 cores were actually doing work. Still, it would be interesting to see just how well or poorly it scales irl.

• tipoo - Sunday, March 13, 2011 - link

  Why would it scale poorly? The 543 is built to be modular, its supposed to scale better than any other GPU solution.

• ncb1010 - Sunday, March 13, 2011 - link

  Imagination Technologies says that the GPU scales at an efficiency of 95% when you add more cores. That is likely the rate of fallof from theoretical 2x performance when you go from 1 to 2 cores and from 2 cores to 4 cores.

• jalexoid - Saturday, March 12, 2011 - link

  Ahem.... Actually GPUs scale almost linearly.

• somata - Sunday, March 13, 2011 - link

  As impressive as the performance of modern low-power GPUs is, it helps to put things in perspective:
  
  Tegra 2 - 4.8 GFLOPS (8, 1-way ALUs @ ~300MHz)
  PowerVR SGX543MP2 - 19.2 GFLOPS (8, 4-way ALUs @ ~300MHz??)
  Radeon 9700 Pro - 33.8 GFLOPS (8, 4-way ALUs (pixel) + 4, 5-way ALUs (vertex) @ 325MHz)
  Radeon 2400 Pro - 42 GFLOPS (8, 5-way ALUs @ 525 MHz)
  Radeon 5450 - 104 GFLOPS (16, 5-way ALUs @ 650MHz)
  Xenos (Xbox 360) - 240 GFLOPS (48, 5-way ALUs @ 500MHz)
  RSX (PS3) - 255.2 GFLOPS (24, 2 x 4-way ALUs (pixel) + 8, 5-way ALUs (vertex) @ 550MHz)
  Radeon 6970 - 2703.4 GFLOPS (384, 4-way ALUs @ 880MHz)
  
  Granted, this only compares theoretical peak shader performance, and doesn't take into account the better ALU utilization of modern designs, but it should roughly correlate with general performance on modern workloads. Note that the iPad's GPU is just starting to approach Radeon 9700 (circa late-2002) levels of performance. It's impressive given the power-profile, but still nowhere near the performance of the 5-year-old consoles, and quite a bit lower than even a very low-end Radeon 2400 Pro from 2007.
  
  The MP4 however, might come close to the Radeon 2400, depending on clocks. Once the next generation of consoles launch (hopefully next year, we'll see at E3) and game graphics likewise catch up to what modern high-end GPUs are capable of, the low-power GPUs will once again be put in their place for a number of years.

• Juzcallmeneo - Sunday, March 13, 2011 - link

  I'm almost positive I saw the XBox GPU scoring like twice the PS3 GPU somewhere..where did you get all these stats? I know the PS3 is capable of more graphics due to it's strange, but amazing CPU..but when comparing only GPU's the XBox's should be stronger.

• tipoo - Sunday, March 13, 2011 - link

  "but when comparing only GPU's the XBox's should be stronger."
  
  Yeah, it probably is. The 360 has a unified shader architecture, so it automatically splits up tasks depending on the workload. The PS3's GPU has fixed function pixel and vertex shaders, meaning all their power might not be used fully at any given point.

• somata - Sunday, March 13, 2011 - link

  I tried to show how I derived all the figures, but perhaps you're questioning the "2 x 4-way ALUs" part that gives the RSX the edge in this comparison. Recall that RSX is based on G70, which had 24 "shader pipelines" and each pipeline had *two* 4-way FMADD units, for a total of 48. The caveat is that the instructions for both units have to come from the same instruction stream, a restriction not shared by Xenos or any other modern ALU organization.
  
  So yeah, the RSX figure is the most optimistic of the bunch. Xenos no doubt sees much better utilization, due to not sharing the above restriction, having unified shaders, and having much better branch performance. In practice I'd say the Xbox 360's GPU has superior shader performance compared to RSX, but RSX does have a bit of a texturing advantage (24 vs 16 TMUs).

• coredump27 - Sunday, March 13, 2011 - link

  "Once the next generation of consoles launch (hopefully next year, we'll see at E3) and game graphics likewise catch up to what modern high-end GPUs are capable of, the low-power GPUs will once again be put in their place for a number of years."
  
  Dream on!
  
  ST Ericsson have announced their Nova A9600 mobile SoC using Imagination Technologies next gen PowerVR Series 6. Sampling later this year the GPU delivers in excess of 210 GFLOPS.
  
  Source - http://www.stericsson.com/press_releases/NovaThor....
  
  "The Nova A9600, built in 28nm, will deliver groundbreaking multimedia and graphics performance, featuring a dual-core ARM Cortex- A15-based processor running up to up to 2.5 GHz breaking the 20k DMIPS barrier, and a POWERVR Rogue GPU that delivers in excess of 210 GFLOPS. The graphics performance of the A9600 will exceed 350 million ‘real’ polygons per second and more than 5 gigapixels per second visible fill rate (which given POWERVR’s deferred rendering architecture results in more than 13 gigapixels per second effective fill rate). Thanks to Rogue Nova will support all existing APIs such as Microsoft DirectX. The Nova A9600 is sampling in 2011."

• somata - Sunday, March 13, 2011 - link

  What's to dream on about? Game consoles being released no later than next year (which may be dreaming given the current climate) or low-power GPUs not being able to catch high-power GPUs?
  
  First of all, 210 GFLOPS is still less than 1/10 of current GPU performance, and you can bet the next-gen consoles will have nothing less powerful than the current top-of-the-line. Again, I'm not dismissing Img. Tech's feat of cramming so much performance into such a small power-envelope, but does anyone realistically expect a sub-1W GPU to be able to take on GPUs that can consume 10s of watts built on the same process? You'll always be able to do more with more.
  
  Lastly, "sampling in 2011" means we'll be lucky to see any shipping devices based on this even next year, especially ones with the "up to" specs mentioned in the PR.