Why non-gaming Windows laptop/tablet throttles due to time limit?

Discussion in 'Mobile Devices and SoCs' started by orangpelupa, May 29, 2021.

  1. orangpelupa

    orangpelupa Elite Bug Hunter
    Legend Veteran

    Joined:
    Oct 14, 2008
    Messages:
    9,402
    Likes Received:
    2,632
    So even when the temperature is cool (e.g. blasting Air Conditioner right to the device), it will still throttles

    This happens in
    • Lenovo Yoga 6 (luckily can be overridden to only throttle by temperature with ryzenadj app)
    • Surface Pro (i think it was 4)
    • Sony Vaio Tap 11
    • Asus vivobook something something
    On the other hand, on "gaming" laptops, they properly throttle to temperature. So if you keep them cool, they are fast.

    any idea why manufacturers did this?
    are non-gaming devices simply so poorly designed (maybe VRMs not designed for sustained load, etc) to chase "thin and light", they need to be time-limited on top of temperature limited?

    dunno this "throttle by time" also happen in macbook, linux laptops, and chromebook or not.
     
  2. iroboto

    iroboto Daft Funk
    Legend Regular Subscriber

    Joined:
    Mar 6, 2014
    Messages:
    13,566
    Likes Received:
    16,624
    Location:
    The North
    I wonder if battery settings are to blame here. Maybe see if you can do something there
     
  3. tongue_of_colicab

    Veteran

    Joined:
    Oct 7, 2004
    Messages:
    3,734
    Likes Received:
    922
    Location:
    Japan
    Are you sure it's not just thermal throttling? Your AC probably isn't blowing 15c air right into the device. Even if it did, I guess the cooling systems in those devices just aren't designed to run at full power the whole time.

    IMHO that makes sense for devices aimed at the average consumer because they generally don't run applications that need to run at full power for extended periods of time.
     
    digitalwanderer likes this.
  4. orangpelupa

    orangpelupa Elite Bug Hunter
    Legend Veteran

    Joined:
    Oct 14, 2008
    Messages:
    9,402
    Likes Received:
    2,632
    I forgot to mention that they were in "performance mode" (each brand got different name for that mode)

    for example on Lenovo Yoga 6, for the first ~2 minutes it will be able to go to 25 watts (temperature around 90c) and then throttles to 15 watts (temperature around 80c).
    But with external cooling to cool down the laptop, it goes ~60c max, and it still throttles to 15 watts after ~2 minutes.

    and yeah, for most people, they only need burst speed.

    im just baffled why manufacturers limits the speed with timer. why not just with temperature.
     
  5. tongue_of_colicab

    Veteran

    Joined:
    Oct 7, 2004
    Messages:
    3,734
    Likes Received:
    922
    Location:
    Japan
    Maybe it's because even if the CPU stays cool, they cannot guarantee the rest of the device stays within design limits when running at 35 watt for over 2 minutes?

    Or maybe it's because the device will become uncomfortably/painfully hot for users to touch? You might be able to keep the CPU cool but all that additional heat will have to go somewhere and not all of it will go straight out of the cooling vents.
     
  6. Malo

    Malo Yak Mechanicum
    Legend Veteran Subscriber

    Joined:
    Feb 9, 2002
    Messages:
    8,377
    Likes Received:
    4,815
    Location:
    Pennsylvania
    Doesn't Intel have a timer for how long their various CPUs are allowed to operate at higher frequencies?
     
  7. orangpelupa

    orangpelupa Elite Bug Hunter
    Legend Veteran

    Joined:
    Oct 14, 2008
    Messages:
    9,402
    Likes Received:
    2,632
    Yeah the other components could be the reason. As for unfomfortable for touch, they're already uncomfortable when they boost inside the time limit haha

    Yep, both Intel and amd got time limit. Customisable by manufacturer
     
  8. Silent_Buddha

    Legend

    Joined:
    Mar 13, 2007
    Messages:
    18,033
    Likes Received:
    8,252
    This is likely mostly due to the assumption that most of the time the device will be used on battery time combined with laziness to properly implement different hardware profiles for battery versus device connected to power. That 2 minute limit is almost purely there to save power as the device will almost always throttle to prevent damage to the CPU if heat got that bad before the 2 minute mark. The provided power supply probably also can't keep the battery charged under full load without that 2 minute throttle. The power supplies chosen are the bare minimum to keep the device charged (IE - cheap)

    That said, some devices do actually implement proper hardware profiles for power and CPU/GPU clocking. For example, my Surface Book 2 with NV GPU. When connected to mains power, it'll happily suck down 100+ watts while gaming for an unlimited duration. Well, except for one major flaw, the provided 102 watt power brick can't provide enough power while gaming so the battery slowly drains while connected if the game heavily uses the GPU. Note that because it's connected to mains power it won't throttle either the CPU or GPU even though the battery will eventually drain down to 0% in a power hungry game. :p

    This was later addressed with a larger wattage power bricks (Surface Book 3 has a 127 watt power supply) and docks (latest one is 199 watts, but not all of it goes to power the Surface device), but I'd have to buy one and I don't seriously game on it much, so I haven't gotten one.

    For gaming laptops the opposite assumption is true, that the device will generally be used while connected to power. Thus there is no consideration WRT serious power savings because it's meant for gaming and reducing power during a game would be really REALLY bad. Hence there is no 2 minute power limit. Instead, the battery will just drain really fast in those situations if not connected to mains power. Also, because of this assumption WRT gaming, they'll generally come with higher wattage power supplies (expensive compared to non-gaming laptops).

    Regards,
    SB
     
    #8 Silent_Buddha, May 30, 2021
    Last edited: May 30, 2021
    orangpelupa likes this.
  9. orangpelupa

    orangpelupa Elite Bug Hunter
    Legend Veteran

    Joined:
    Oct 14, 2008
    Messages:
    9,402
    Likes Received:
    2,632
    yep, the performance is exactly the same between plugged-in and on battery. The max input of the laptop = 45 watts, and the max output of the charger also 45 watts. so there's no overprovisioning at all.
     
  10. eastmen

    Legend Subscriber

    Joined:
    Mar 17, 2008
    Messages:
    12,720
    Likes Received:
    3,646
    The pro 4 unless you have the i7 version doesn't have active cooling
    [​IMG]
     
  11. Albuquerque

    Albuquerque Red-headed step child
    Veteran

    Joined:
    Jun 17, 2004
    Messages:
    3,924
    Likes Received:
    456
    Location:
    35.1415,-90.056
    I know this thread is a week or two old, however this is the correct answer to OP's question.

    The turbo boost function has a specific time limit, unrelated to temperature. The default is configured in the firmware of your system, and depending on the vendors choices, could be potentially overridden with a tool such as ThrottleStop. I use ThrottleStop on my Gigabyte Aero 15x laptop for three reasons:
    • Undervolt the i7-8750H CPU and related 630 iGPU. This provides two linked benefits: reduced thermals and additional power headroom. Both combined permit my laptop to hit the top all-core boost bin (4.1GHz) continuously if I want the full power of the CPU. It couldn't keep this boost bin in stock form because it would get too hot and throttle...
    • Next is extending the boost time and power limits to functionally unlimited. In reality the values are something like 42 days as the upper time limit, and around 90A is the power limit -- which is pointless because the CPU doesn't consume that much power at full boost bin anyway.
    • Finally is the ability to pick up four configurable power settings for different needs. On AC, I've configured ThrottleStop to limit my CPU to around 15A, which is enough for about 2.2GHz all-core, or about 3.3GHz four core, or the full boost 4.1GHz dual core. What I've discovered is, these clocks are just about right for basically every game I play, because I'm almost always GPU limited by the 1070 MaxQ GPU. Accordingly, with the CPU limited to just 15A, I have all the thermal headroom I need to allow the GPU to hit its own top boost bins without throttling due to heat. I also have other configurations, such as a full-CPU-power mode which employs a 50A CPU power limit but way underpowers the iGPU so I can do CPU intensive things. I then have a battery profile which isn't much different than the AC profile, but now clamped down to 10A CPU. And then there's an extreme battery profile that kicks in at 20% battery life remaining, which has basically everything choked out lol.

    If you want to be a power laptop user, this is the way. :) ThrottleStop (9.3.1 Beta) Download | TechPowerUp (don't actually download the beta, just get the 9.3 "production" release. It's all the same webpage tho)
     
    pharma likes this.
Loading...

Share This Page

  • About Us

    Beyond3D has been around for over a decade and prides itself on being the best place on the web for in-depth, technically-driven discussion and analysis of 3D graphics hardware. If you love pixels and transistors, you've come to the right place!

    Beyond3D is proudly published by GPU Tools Ltd.
Loading...