Samsung Galaxy S21 Ultra 5G review

Performance and benchmarks

As it is always with Samsung flagships, the Galaxy S21 trio is sold with 2 chipset variants with specific regions getting one or the other. North America and China receive the Snapdragon 888 from Qualcomm, while handsets for the rest of the world are equipped with Samsung's latest Exynos 2100 SoC.

Note20 Ultra and S21 Ultra

The processors in both chips have a tri-cluster arrangement and use the same cores (Qualcomm is said to have tweaked things in the prime core). Headlining these processors is ARM's Cortex-X1, a no-compromise performance-focused design based on the Cortex-A78. Next up is a trio of Cortex-A78s, regular ones, while four Cortex-A55s for more mundane tasks take the total core count to eight.

For all the sameness in the setup, there is a difference in the clock rates, which is somewhat significant. The Exynos numbers read 1x2.9GHz + 3x2.8GHz + 4x2.2GHz, while the Snapdragon spec sheet says 1x2.8GHz + 3x2.4GHz + 4x1.8GHz, and the higher rates may give the Samsung chip advantage for applications that can make good use of multiple cores. For comparison, the Kirin 9000 uses the older Cortex-A77 cores in the performance cluster, but its prime core is ticking higher than either the SD888's or the E2100's (1x3.13GHz Cortex-A77 + 3x2.54GHz Cortex-A77 + 4x2.05GHz Cortex-A55).

On the GPU front, the Snapdragon comes with the Adreno 660 GPU, which Qualcomm says is 35% faster and 20% more energy-efficient than last year's Adreno 650.

The Exynos 2100 employs a Mali-G78 GPU with 14 cores and promises 46% improvement over the last generation. The GPU in the Kirin 9000 has the same Mali GPU but in a maxed-out 24-core configuration, though probably at a lower clock rate.

Both the SD888 and the E2100 are manufactured by Samsung on a 5nm fabrication line - Qualcomm switched from TSMC to Korean foundries for this year's chips' production.

There is 12GB LPDDR5 RAM on either version. If you think that'd be insufficient, you can also get the largest storage model, which employs a whopping 16GB RAM. Storage is always UFS 3.1, and three options are available - 128GB, 256GB or 512GB.

Our Galaxy S21 Ultra review unit has the Exynos chipset inside and has 256GB of storage and 12GB RAM.

Geekbench is a CPU benchmark, and it puts the single-core Cortex-X1 core on top of every other Android phone we've tested to date, better than the Cortex-A77 inside the Huawei Mate 40 Pro. We don't have a Snapdragon 888 reference just yet, though we hope we'll get our hands on the Xiaomi Mi 11 soon enough.

The Apple's latest Firestorm core is still on top with an unfathomable lead, not that it matters that much, though.

GeekBench 5 (single-core)

Higher is better

• Apple iPhone 12 Pro Max
  1606
• Samsung Galaxy S21 Ultra 5G
  1107
• Samsung Galaxy S21 5G
  1032
• Huawei Mate 40 Pro (perf. mode)
  1020
• Huawei Mate 40 Pro
  920
• Galaxy S20 Ultra 5G (60Hz, 1440p)
  910
• Samsung Galaxy S20 FE
  906
• Galaxy S20 Ultra 5G (120Hz, 1080p)
  904
• Xiaomi Mi 10 Ultra
  901
• Huawei P40 Pro+
  781

It's a bit different picture on the multi-core test. When running in Performance mode, the Huawei Mate 40 Pro beat the current Exynos, but that's not sustained performance. The combined score isn't significantly better than the Snapdragon 865, but it is quite the improvement over the S20 Ultra's Exynos 990.

GeekBench 5 (multi-core)

Higher is better

• Apple iPhone 12 Pro Max
  4240
• Huawei Mate 40 Pro (perf. mode)
  3704
• Samsung Galaxy S21 Ultra 5G
  3518
• Samsung Galaxy S20 FE
  3296
• Huawei Mate 40 Pro
  3275
• Xiaomi Mi 10 Ultra
  3248
• Samsung Galaxy S21 5G
  3238
• Huawei P40 Pro+
  3203
• Galaxy S20 Ultra 5G (60Hz, 1440p)
  2728
• Galaxy S20 Ultra 5G (120Hz, 1080p)
  2697

The raw GPU power is a lot, and the Galaxy S21 Ultra tops our offscreen Car Chase test. Well, unless we count the iPhone, that is. Anyway, the new Exynos's GPU is about 25% more powerful than the GPU inside the old Exynos 990 (Galaxy S20 Ultra) and the Snapdragon 865 (Galaxy S20 FE).

GFX Car Chase ES 3.1 (offscreen 1080p)

Higher is better

• Apple iPhone 12 Pro Max
  78
• Samsung Galaxy S21 Ultra 5G
  64
• Huawei Mate 40 Pro (perf. mode)
  64
• Huawei Mate 40 Pro
  56
• Samsung Galaxy S21 5G
  54
• Samsung Galaxy S20 FE
  52
• Galaxy S20 Ultra 5G (120Hz, 1080p)
  51
• Galaxy S20 Ultra 5G (60Hz, 1440p)
  51
• Xiaomi Mi 10 Ultra
  51
• Huawei P40 Pro+
  44

The Galaxy S21 Ultra is the only QHD phone among the new Galaxy S21 series, though, and when the GPU is engaged displaying 1440p games, the S21 Ultra frame rate drops. The score is still quite respectable, of course.

GFX Car Chase ES 3.1 (onscreen)

Higher is better

• Samsung Galaxy S21 5G
  60
• Apple iPhone 12 Pro Max
  55
• Xiaomi Mi 10 Ultra
  46
• Samsung Galaxy S20 FE
  45
• Galaxy S20 Ultra 5G (120Hz, 1080p)
  43
• Huawei Mate 40 Pro (perf. mode)
  43
• Samsung Galaxy S21 Ultra 5G
  33
• Huawei P40 Pro+
  31
• Galaxy S20 Ultra 5G (60Hz, 1440p)
  25
• Huawei Mate 40 Pro
  25

The S21 Ultra's Antutu result is the best we've had to date unless we count the Mate 40 Pro's result achieved with some trickery. The S21 Ultra managed to beat the Galaxy S21 and the previous S20 devices by a lot. It's also beaten the iPhone 12 Pro Max!

AnTuTu 8

Higher is better

• Huawei Mate 40 Pro (perf. mode)
  686835
• Samsung Galaxy S21 Ultra 5G
  657150
• Apple iPhone 12 Pro Max
  638584
• Xiaomi Mi 10 Ultra
  638497
• Samsung Galaxy S21 5G
  584055
• Samsung Galaxy S20 FE
  543986
• Huawei Mate 40 Pro
  531270
• Huawei P40 Pro+
  529687
• Galaxy S20 Ultra 5G (60Hz, 1440p)
  528631
• Galaxy S20 Ultra 5G (120Hz, 1080p)
  514485

The Galaxy S21 Ultra has the most powerful hardware so far, so without a doubt, it is and will continue to be a powerhouse for the next couple of years. Things are done effortlessly on the Ultra, no matter the app or game, resolution and frame rate.

The Ultra has a sharp 1440p display, which requires more power running games in native mode, and while the phone scores lower on the GPU tasks (compared to 1080p phones) - do not worry; its game performance is still excellent.

We also ran the Wild Life Stress Test within the 3D Mark app, and the S21 Ultra scores a 70% stability rating. It runs rather nice and cool for the first 13 of 20 loops, but its performance degrades from there on as the phone starts throttling to battle the higher temperatures. It gets warm, not hot, and this is after 15 mins of non-stop GPU usage at 100%. This is not representative of real-life gaming, though it's good to know the chipset's threshold.

In real life, we couldn't reach the point where we'd notice throttling, not even when running a game for a long time. And that's more than enough by our books to be happy with the performance and the power management.