Why does refresh rate have such a large impact on power consumption? I understand that the control electronics are 60x more active at 60 Hz than 1 Hz, but shouldn't the light emission itself be the dominant source of power consumption by far?
High pixel density displays have disproportionately higher display refresh power (not just proportional to the total number of pixels as the column lines capacitances need to be driven again for writing each row of pixels). This was an important concern as high pixel densities were coming along.
Display needs fast refreshing not just because pixel would lose charge, but because the a refresh can be visible or result in flicker. Some pixels tech require flipping polarity on each refresh but the curves are not exactly symmetric between polarities, and further, this can vary across the panel. A fast enough refresh hides the mismatch.
Not my field so please forgive a possibly obvious question: That seems true regardless of the pixel count (?), so for that process why wouldn't power also be proportional to the pixel count?
I notice I'm saying 'pixel count' and you are saying 'pixel density'; does it have something to do with their proximity to each other?
You don’t need to render 60 times the same frame in software just to keep that visible on screen.
The connection between the GPU and the display has been run length encoded (or better) since forever, since that reduces the amount of energy used to send the next frame to the display controller. Maybe by "1Hz" they mean they also only send diffs between frames? That'd be a bigger win than "1Hz" for most use cases.
But, to answer your question, the light emission and computation of the frames (which can be skipped for idle screen regions, regardless of frame rate) should dwarf the transmission cost of sending the frame from the GPU to the panel.
The more I think about this, the less sense it makes. (The next step in my analysis would involve computing the wattage requirements of the CPU, GPU and light emission, then comparing that to the KWh of the laptop battery + advertised battery life.
> LG Display is also preparing to begin mass production of a 1Hz OLED panel incorporating the same technology in 2027.
The LG press release states that it's LCD/TFT.
https://news.lgdisplay.com/en/2026/03/lg-display-becomes-wor...
And yet, it’s the fundamental technology enabling always on phone and smartwatch displays
The intent of this is to reduce the time that the CPU, GPU, and display controller is in an active state (as well as small reductions in power of components in between those stages).
But the article is about an OLED display, so the pixels themselves are emitting light.
The article is about an LCD display, actually.
The Apple Watch Series 5 (2019) has a refresh rate down to 1Hz.
M4 iPad Pro lacks always-on display despite OLED panel with variable refresh rate (2024):
https://9to5mac.com/2024/05/09/m4-ipad-pro-always-on-display...
I'm not sure that there's really anything new here? 1Hz might be lower. Adoption might be not that good. But this might just be iteration on something that many folks have just not really taken good advantage of till now. There's perhaps signficiant display tech advancements to get the Hz low, without having significant G-Sync style screen-buffers to support it.
One factor that might be interesting, I don't know if there's a partial refresh anywhere. Having something moving on the screen but everything else stable would be neat to optimize for. I often have a video going in part of a screen. But that doesn't mean the whole screen needs to redraw.
CRTs needed to be refreshed to keep the phosphors glowing. But all screens are now digital: why is there a refresh rate at all?
Can’t we memory-map the actual hardware bits behind each pixel and just draw directly (using PCIe or whatever)?
Assuming the xps has the same size battery, and this really reduces power consumption by 48%, I'd expect 16 hours real world, 32 in benchmarks and 48 in some workload Dell can cherry pick.
Less of a problem for iphones that unlikely to stay for a week in the same place plugged in and unused.
Brightness, Uniformity, Colour Accuracy etc. It is hard as we take more and more features for granted. There is also cost issues, which is why you only see them in smaller screens.
The ability to vary it seems like it would be valuable as there are significant portions of a screen that remain fairly static for longer periods but equally there are sections that would need to change more often and would thus mess with the ability to stick to a low rate if it's a whole screen all-or-nothing scenario.
For example:
- reading an article with intermittent scrolling
- typing with periodic breaks
I remember playing with it a bit, and it would dynamically change to a high refresh rate as you moved the mouse, and then drop down as soon as the mouse cursor stopped moving.
I had issues with it sometimes being lower refresh rate even when there was motion on screen, so the frame rate swings were unfortunately noticeable. Motion would get smoother for all content whenever the mouse moved.
1hz is drastically fewer refreshes. I hope they have the “is this content static” measurement actually worked out to a degree where it’s not noticeable.
I don't think you could divide vertically though.
Don't think anyone has done this yet. You could be the first.
Ignoring switching costs, keeping a sample-and-hold LED at 0%, 50% and 100% brightness all cost zero energy. For an OLED, the costs are closer to linear in the duty cycle (again, ignoring switching costs, but those are happening much faster than the framerate for OLED, right?)
(Also, according to another comment, the panel manufacturer says this is TFT, not OLED, which makes a lot more sense.)
I'm not even sure how they got their 48% figure. Sounds like a whole-system measurement, maybe that's the trick.
What's new here is the 1 Hz minimum.
But to the rest of the world variable refresh rate existed for years by then. As is with most Apple "inventions".
In this case the patent goes back to 1982: https://patents.google.com/patent/US4511892A/en
So it makes sense you could cut the refresh time down to a second to save power...
Although one wonders if it's worth it when the backlight uses far more power than the control electronics...
With conventional PSR, I think the goal is to power off the link between the system framebuffer and the display controller and potentially power down the system framebuffer and GPU too. This may not be beneficial unless it can be left off long enough, and there may be substantial latency to fire it all back up. You do it around sleep modes where you are expecting a good long pause.
Targeting 1 Hz sounds like actually planning to clock down the link and the system framebuffer so they can run sustain low bandwidth in a more steady state fashion. Presumably you also want to clock down any app and GPU work to not waste time rendering screens nobody will see. This seems just as challenging, i.e. having a "sync to vblank" that can adapt all the way down to 1 Hz?
I was under the impression that modern compositors operated on a callback basis where they send explicit requests for new frames only when they are needed.
24Hz - now you can correctly play movies.
30Hz - NTSC (deinterlaced) including TV shows + video game emulators.
50Hz - (24 * 2 = 50 in Hollywood. Go look it up!) Now you can correctly play PAL and movies.
120Hz - Can play frame-accurate movies and NTSC (interlaced or not). Screw Europe because the judder is basically unnoticeable at 120Hz.
144Hz - Can play movies + pwn n00bs or something.
150Hz - Unobtanium but would play NTSC (deinterlaced), PAL and movies with frame level accuracy.
240Hz - Not sure why this is a thing, TBH. (300 would make sense...)
> Source: https://www.pcworld.com/article/3096432 [2026-03-23]
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> HKC has announced a new laptop display panel that supports adaptive refresh across a 1 to 60Hz range, including a 1Hz mode for static content. HKC says the panel uses an Oxide (metal-oxide TFT) backplane and its low leakage characteristics to keep the image stable even at 1Hz.
> Source: https://videocardz.com/newz/hkc-reveals-1hz-to-60hz-adaptive... [2025-12-29]
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> History is always changing behind us, and the past changes a little every time we retell it. ~ Hilary Mantel
Ok, that makes some amount of sense. The article claims this is an OLED display, and I haven't heard of significant power games from low-refresh-rate OLED (since they have to signal the LED to stay on regardless of refresh rate).
However, do TFT's really use as much power as the rest of the laptop combined?
They're claiming 48% improvement, so the old TFT (without backlight) has to be equivalent to backlight + wifi + bluetooth + CPU + GPU + keyboard backlight + ...
level of what? Power consumption? dude e-ink takes 0 power between refreshs.
And e-ink is pretty?
There are also mini LED laptop for creative work. Few more things to check before buying new laptop.
- The LEDs for a mostly dark region with a point source are too bright so the point source is the correct brightness. Benchmark sites call this "blooming" and ding displays for it, so new ones pick the other problem:
- The LEDs for mostly dark regions with a point source are too dim so the black pixels don't appear gray. This means that white on black text (like linux terminals) render strangely, with the left part of the line much brighter than the right (since it is next to the "$ ls" and "$" of the surrounding lines). Also, it means that white mouse pointers on black backgrounds render as dark gray.
For creative work, I'd pick pretty much any other monitor technology (with high color gamut, of course) over mini LED. However mini-LED is great if you have a TV that is in direct sunlight, since it can blast watts at the brightest parts of the screen without overheating.
I'm not sure if this LG display will have the same issue, but I won't be an early adopter.
The display has a refresh rate of 120hz when needed. The low refresh rate is for battery savings when there is a static image.
Variable refresh rate for power savings is a feature that other manufacturers already have (apple for one). So you might already be an early adopter.
Saving battery is nice, but I'm not leaving Linux for that misery any time soon
Apple already uses similar tech on the phones and watches.
The idea of having a 60Hz screen is nice, but in practice it turns out that display refresh rate is not the bottleneck for most software.
