JULY 2020 PCWorld 81to explain. Panels with 1920x1080 resolution
are inexpensive, look decent on smaller
screens, and are battery-efficient. IT
departments also appreciate 1080p because
it generally works with any application, with
no scaling issues. That makes it a safe bet for
the commercial laptop market.
“FHD, that’s the easy one,” Butler said in
an interview. “That has become the industry
sweet spot.”
But as laptop makers have moved into
higher resolutions, they’ve gravitated toward
3840x2160, or 4K resolution, skipping over
anything in between. That’s largely because
of the hype that TV manufacturers have
created around 4K. “The TV industry has really
trained consumers to look for 4K,” Butler said.
The problem is that 4K displays affect
laptops in a way that users don’t experience
with 4K TVs. “TVs aren’t bound by battery
life,” Butler pointed out.
Compared to 1080p, 4K panels
have four times as many pixels.
Lighting them up requires much
more powerful backlighting. The
laptop’s processor also has to work
harder to render images with all
those extra pixels.
The results are clear: In review
after review, we’ve found that 4K
displays create a serious drag on
battery life. Lenovo’s ThinkPad X1
Carbon 7th Gen (go.pcworld.
com/x1c7), for instance, lasted just
6 hours and 9 minutes in our battery rundown
test with a 4K display. The previous version of
the X1 Carbon, with a 1080p display, lasted 8
hours and 48 minutes in the same test. In
terms of advertised battery life, Lenovo’s Yoga
C940 14 (go.pcworld.com/yc94) promises
15 hours with a 1080p display, and just 10
hours with 4K. (In real-world use, you can
expect battery life to be roughly cut in half.)
PCWorld has also found that Intel’s
integrated graphics can struggle with 4K
displays, making otherwise nice laptops like
the Dell Inspiron 15 7000 (go.pcworld.com/
in70) exhibit jumpy scrolling and choppy
animations. Discrete graphics cards do a
better job, but they put an even bigger strain
on battery life. Most laptop graphics cards
can’t really handle 4K gaming anyway.
Despite those deficiencies, display
manufacturers have focused more on 4K thanWe’ve found that 4K displays seriously affect the battery life of
laptops like Lenovo’s ThinkPad X1 Carbon 7th Gen (pictured).