How did reviewers with the 7840 + 2.8K Screen get 12 hours of battery!? I'm nonly getting 3-5!

Admittedly, I should’ve bought it new so I could return it but my only choices now are to resell or learn to live with it and I’d much rather not sell but I really need advice on how to deal with this thing.

I’ve followed the wiki and even tried commands to limit boosting but my battery just seems to have gotten worse. 7hrs was my average under ubuntu and but 5 hours is my maximum now. I’m not trying to say non-soldered ram is the issue because Lenovo Legions & HP Omen 14s with a dedicated GPU + Oled Screens are getting 10-12 hours of battery for cheaper.

I want to support the mission but I’m really feeling like something’s screwed in their bios causing this.

That certainly isn’t all on the soldered ram, that stuff makes the difference between 20h and 30h not 5h and 12h.

Are you running the new screen at 120hz all the time?

well, they set some parameters very low so they can do the same test with multiple devices. Some laptops’ displays barely reach 200 nits brightness, so they set that to 200 nits when testing battery. I don’t know where one would use such brightness, maybe in complete darkness, cause I can’t see anything on my display in my room if it is below 300 nits. Not even mentioning outside use. Display brightness alone can add multiple hours to battery life.

Then, they do very basic, repeated tasks. None of which is actual use case (unless you want to be braindead on youtube for 10 hours at 480p).

In actual use case, when I work, I tend to only use apps required for work. No youtube in the background, no music. My phone provides me with audio of whatever I need. Video (especially good quality video) consumes a lot of power. There you can save couple of hours.

These benchmarks are there to compare your own device with others, not actual use-case.

I rarely use displays above 100nits, if there is sun I go somewhere else XD.

That is a use-case for a laptop though, with or without the braindead or 480p parts.

Especially in a browser, though that got a lot better since the thing first came out.

A reduction from 7h to 5h could very well be explained by the display running at 120hz and keeping the ipu awake a lot more though.

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Don’t have the 7840+2.8k screen but the answer to your question is almost always the same. They don’t crank up the display to 100% brightness, and watch 4k video the whole time…really the only way you are going to be cranking the power usage past 10-12w on average. Whatever you have done, or followed to get you that abysmal power usage, check it over you likely did something wrong.

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An item, potentially worth noting.. The battery on the 7840 w/ the 2.8k screen ‘was’ the 61 WH model, no? Is it possible that the battery is in that failure condition where it is starting to swell? Being second hand, I’d not be surprised if it was sold because of that specifically.

I’d take the cover off to investigate, and if that is not the case, I’d pull the battery life figures.. Depending on the use case of the previous owner, they might have burned right through most of the cycles already.

I get currently get 6 hours on average with Windows, with the variable refresh rate option on. That’s at a current battery capacity of 54 Wh, whereas if it was at design capacity Windows said it would be roughly 6:40. I got roughly 2 extra hours of battery before I switched to the higher resolution / higher refresh rate screen.

Unfortunately, there’s a ton of factors which could play into this too, including (but not limited to) which expansion cards you’re using and which slots they’re in. But overall, it just seems like this is not that efficient of a chip for real-world use.

OP can separate the conditions by:

Use btop and observe the instantaneous power drain when doing various tasks. And use $ upower -i $(upower -e | grep battery) to check the battery health.

In this way the reason(s) of short duration can be known

With adaptive sync. So it drops to 30hz when static

Additionally, the 61wh is a brand new battery that I bought for myself and recycled the original one and it has 8 charge cycles so far.

Are you on Linux or Windows?

If you are on Linux, make sure that you are using hardware accelerated video playback on Firefox/Chromium. Make sure that you are using software like power-profiles-daemon or tuned in order to set system performance.

I have noticed that Windows in general has better battery life compared to Linux. This is with my system having all of the performance stuff set via powertop, tuned, and custom udev rules.