Power Consumption

On AMD’s official specifications for the Ryzen 9 6900HS, it lists the TDP as 35 W: the same specifications as the 6900HX, but at an optimized TDP. The HS means that it can only be used in AMD-approved and codesigned systems that can get the best out of the unit: i.e. it is an ultraportable premium device. That being said, laptop vendors can customize the actual final power limit as high as 80W, with the idea that because they are using an optimized voltage/frequency binned processor, the laptop design that can dissipate that much can extract more sustained performance from the processor, this usually translates into a higher all-core frequency.

For our ASUS Zephryus G14, the standard default power profile, known as ‘Performance’, is meant to conform to AMD’s Power Management Framework, i.e. scale from Energy Saving to Performance as required. In this mode, the system has a sustained 45 W power draw.

Performance: 45W

Loading up a render like POV-Ray, the system spikes the CPU package power to 83 W and 80ºC, before very quickly coming down to 45 W and a slowly rising temperature to equilibrium at 87ºC.

With something a bit more memory heavy, such as yCruncher, the same power profile is shown, this time with the power around about 81ºC for most of the test because it spends more time on memory access than raw throughput.

For a real-world scenario, Agisoft also spikes up very high initially, before reaching a plateau at 45 W and 90ºC.

Turbo: 65W

The other option on offer for this system is the ‘Turbo’ Mode, which jacks everything up to 65 W sustained.

This means we hit the peak temperature limits quite quickly, and the system ramps down over time to the 65 W average power.

The yCruncher profile is a bit more varied due to the CPU performance going further while the memory performance staying the same, but we still see temperatures in the mid 90s and power hovering more around 75 W.

Agisoft’s Turbo profile is all about being temperature limited in this case, and we still end up in the sustained parts of the test around that 65 W value.

If we were to look at how the power was distributed in each mode:

In performance mode, we see 16.0 watts when one core is loaded, going down to 5.2 watts per core when all cores are loaded and a frequency of 3775 MHz.

Compare that to the Turbo Mode:

The single-core data is the same, nothing changes there, but we’re now up to 7.2 watts per core when fully loaded, and a much higher frequency at 4050 MHz. But this means we’re using 17 watts more power (or 38% more power) for only 275 MHz (a 7% gain).

Looking at the frequencies in this format, you can see a slight difference in performance, but seemingly not that much to justify the power difference. Then again, I suspect Turbo is only really for when you are fully charged and plugged into mains power anyway.

For the following benchmarks, we’re going to be using both Performance and Turbo modes, but also I put the CPU in a 35W power mode. As the 1 core and 2 core loading is below this, it shouldn’t affect the single-core performance that much, but it might give us an understanding of where it compares to previous generations.

Core-to-Core, Cache Latency, Ramp Performance Per Watt
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  • web2dot0 - Wednesday, March 2, 2022 - link

    PC fanbois would pretend M1 isn't in the convo.

    😆

    They will just tell you that nobody cares about performance per watt... because they said so.
  • Qasar - Wednesday, March 2, 2022 - link

    and the apple fanboys just keep talking about the m1 like its the best things since sliced bread, whats your point ?
    bottom line is this, IF you are already using the over priced apple eco system, then the m1 makes sense, if not, then there is no point to it. i only know 3 people that have either an ipad, or a mac based comp, the rest wont touch apple cause of the price, too expensive for what they would need it for, windows based products, suit their needs just fine.
  • schujj07 - Wednesday, March 2, 2022 - link

    For sure Apple is way too expensive for what you get. Working in industry I hate it when I have to give support to someone using a Mac because the VPN we send them doesn't work. Of the hundreds of VPNs I have sent to people, less then 10 have responded to me saying they need the one for Mac. Mac just doesn't play as nicely with the things we use in a lot of IT.
  • Obiwanbilly - Friday, March 4, 2022 - link

    Oh, the VPN doesn’t work? I have an M1 MacBook Air and I use WireGuard for my VPN. It works perfect!

    Oh 🤔, do you mean “Legacy” VPNs, that are based on IPSEC or OpenVPN? You know, the one’s where Wikipedia says, “… are often complex to set up, disconnect easily (in the absence of further configuration), take substantial time to negotiate reconnections, may use outdated ciphers, and have relatively massive code bases of over 400,000 and 600,000 lines of code, respectively, which hinders debugging.“

    That one? 👆😱

    Hey bro, some of us Mac users are “Pros” too. Maybe you should stop using legacy VPN software and switch to something better? Instead of blaming Macs! 🤦‍♂️

    Obiwanbill

  • BushLin - Friday, March 4, 2022 - link

    Try connecting to your employer's VPN, chances are that it's not wireguard.
  • Obiwanbilly - Friday, March 4, 2022 - link

    Yep, it’s legacy. It needs to be upgraded. I can help, if you want. 😬

    I don’t know why you would continue to use OpenVPN or IPSec. I first used that tech like 14 yrs ago. Move on! 🤓

    Go research the benefits of using WireGuard. It’s a waaaay better solution. Dropped connections on IPSec or Open VPN take FOREVER to reconnect. You don’t need licenses, you can support unlimited users. Your limitation is the hardware you choose to host your WireGuard Server endpoint. WireGuard supports Windows and Android endpoint client devices. Oh yeah, and Mac OS too. 🥳

    ObiwanBilly
  • Dug - Friday, March 11, 2022 - link

    Then you have an outdated or crappy vpn. Every industry standard has a mac client that works fine. Even Azure has a mac configuration for mac vpn.
  • wolfesteinabhi - Wednesday, March 2, 2022 - link

    it will be in convo when Apple starts selling Windows "PC" with M1 in it. till then its definitely not in Convo.
  • tyger11 - Thursday, March 3, 2022 - link

    OS X is enough to keep me away from that hardware, so it doesn't matter.
  • GeoffreyA - Thursday, March 3, 2022 - link

    Frieza's stronger than Goku right now---

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