The Snapdragon 888 vs The Exynos 2100: Cortex-X1 & 5nm - Who Does It Better?
by Andrei Frumusanu on February 8, 2021 3:00 AM EST- Posted in
- Mobile
- Samsung
- Qualcomm
- Smartphones
- SoCs
- Snapdragon 888
- Exynos 2100
5nm / 5LPE: What do we know?
Starting off with the biggest new change of this generation, both the Snapdragon 888 and the Exynos 2100 are manufactured on Samsung’s new 5nm process node, which is the biggest unknown in today’s comparison.
What’s important to remember is that although Samsung calls this node 5nm, its design and characteristics are more similar to that of their 7nm node. Key new characteristics of the new node here are the reintroduction of single diffusion breaks (SDB) on an EUV process node, as well as slight changes in the cell libraries of the process.
Advertised PPA Improvements of New Process Technologies Data announced by companies during conference calls, press briefings and in press releases |
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7LPP vs 10LPE |
6LPP vs 7LPP |
5LPE vs 7LPP |
3GAE vs 7LPP |
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Power | 50% | lower | 20% | 50% | ||
Performance | 20% | ? | 10% | 35% | ||
Area Reduction | 40% | ~9% | <20% | 40% |
Per Samsung’s own numbers, the foundry claims that 5LPE is either 20% lower power than 7LPP, or 10% more performance. These are actually quite important figures to put into context, particularly when we’re comparing designs which are manufactured on TSMC’s process nodes.
In least year’s review of the Galaxy S20 series and the Exynos 990 and Snapdragon 865 SoCs, an important data-point that put things into context was Qualcomm’s Snapdragon 765 SoC which was also manufactured on Samsung’s 7LPP node, and featuring Cortex-A76 cores. In that comparison we saw that The Exynos 990 and the Snapdragon 765’s A76 cores behaves very similarly in terms of power consumption, however they fell behind TSMC-based Cortex-A76 cores by anywhere from 20% to 30%.
In that context, Samsung’s 5LPE process node improving power by 20% would mean they’d only be catching up with TSMC’s 7nm nodes.
An interesting comparison to make – and probably one of the rare ones we’re actually able to achieve today, is the comparison between the Cortex-A55 cores inside of both the Snapdragon 865 and the new Snapdragon 888. Both SoCs feature the same IP cores, clock them at the same 1.8GHz frequency, and both feature the same amount of L2 cache, with their only real difference being their process nodes.
Using SPEC’s 456.hmmer – because it’s a workload that primarily resides in the lower cache hierarchies and thus, we avoid any impact of the possibly different memory subsystem, we can see that both SoCs’ power consumption indeed is almost identical, with performance also being identical with a score of 6.84 versus 6.81 in favour of the new Snapdragon 888.
So at least at first glance, our theory that Samsung’s 5LPE merely just catches up with the power consumption and power efficiency of TSMC’s N7/N7P nodes seems to be valid – at least at these frequencies.
Further interesting data is the voltage curves of the CPUs on the Exynos 2100. I’ve extracted the frequency voltages tables of both my devices, a regular S21 and an S21 Ultra, with the above curves being the better binned chip inside of the smaller S21.
Generationally, Samsung seems to have been able to greatly reduce voltages this generation. On the Cortex-A55 cores, the cores now only require 800mV at 2GHz whilst the Exynos 990 last year in our review unit they required over 1050mV. Similarly, although the comparison isn’t apples-to-apples, the Cortex-A78 cores at 2.5GHz only require 862mV, while the Cortex-A76 cores of the previous generation required also 1050mV.
What’s also very interesting to see is the voltage curves of the Cortex-X1 cores versus the Cortex-A78 cores: they’re both nigh identical to each other, which actually lines up with Arm’s claims that the new X1 cores have the same frequency capabilities as the A78 cores, only being larger and increasing their power consumption linearly in relation to their frequency.
Samsung’s frequency tables indicate that they had been testing the A55 up to 2.6GHz, and the X1 and A78 cores up to 3.2GHz – however voltages here are quite higher and it’s also likely SLSI wouldn’t have been able to achieve similar chip yields.
Unfortunately, I wasn’t able to extract data from my Snapdragon 888 S21 Ultra, so I can’t tell exactly where it falls in terms of voltages compared to the Exynos 2100. One thing I can confirm as being quite different between the two SoCs is that Samsung does actually give the Exynos 2100’s Cortex-X1 core its own dedicated voltage rail and PMIC regulator, while the Snapdragon 888 shares the same voltage rail across the X1 and A78 cores. In theory, that could mean that in more mixed-thread workloads, the Exynos has the opportunity to be more power efficiency than the Snapdragon 888.
Generally, the one thing I want people to take away here is that although Samsung calls this their 5nm node, it’s quite certain that it will not perform the same as TSMC’s 5nm node. Usually we don’t care about density all too much, however performance and power efficiency are critical aspects that effect the silicon and the end-products’ experiences.
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Kishoreshack - Thursday, February 11, 2021 - link
Yeah they doBut Anand & Brian Klugs podcasts were the one which attracted me a lot
The best part was how well Anand designed the bench
Some Anandtech podcasts is required now
Kishoreshack - Monday, February 8, 2021 - link
Soo next year are we gonna have Snapdragon flagship at a better process node or not?There is absolutely no compulsion for Qualcomm to push for a better process node
Apple will run with things
SarahKerrigan - Monday, February 8, 2021 - link
Oof. Those numbers are rough, and not a good look at all for 5lpe.Wonder if we'll see X1/A78 on N5 any time soon. With Hisilicon out of the picture, who would even be the obvious candidate for that? Mediatek?
Spunjji - Monday, February 8, 2021 - link
Mediatek would be an odd candidate, given their tendency to focus on area efficiency, but it'd be a nice surprise if they branched out a bit!lmcd - Monday, February 8, 2021 - link
Yea they'd definitely skip the X1 core. Which honestly might be the correct move based on results, the X1 is better but maybe not enough better to justify the die space.Spunjji - Thursday, February 11, 2021 - link
It certainly seems like it would make more sense on an SoC design aimed at larger devices.geoxile - Monday, February 8, 2021 - link
My experience with Samsung Electronics was heavy use of outsourcing and indian workers, on their software side. I wouldn't be surprised if that's the case for their hardware too. Very poor results for their 5lpe vs TSMC's N7. They're becoming obsessed with cutting costs.iphonebestgamephone - Monday, February 8, 2021 - link
Why would being indian be the reason?jospoortvliet - Wednesday, February 10, 2021 - link
It wouldn't but they aren't local to South Korea, and India has a lot of IT competence so it is a place many companies outsource to.... and outsourcing usually doesn't help quality.iphonebestgamephone - Monday, February 15, 2021 - link
You get what you pay for ofc.