The Pixel 4’s screen refresh rate drops from 90Hz to 60Hz when you dim the display

One of the Google Pixel 4’s headline features is its much-lauded “fast and responsive” 90Hz display, but a user has just found out something huge about the way it works.

The refresh rate automatically switches from 90Hz to 60Hz when screen brightness drops below 75%. That’s something Google didn’t mention at the handset’s unveiling.

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Reddit user OrganicNebula first made the discovery, and it was quickly confirmed by XDA Developers editor-in-chief Mishaal Rahman.

It’s almost certainly there as a battery-saving feature, but it would have been nice if Google had been upfront about the functionality. Or, you know, loaded the Pixel 4 with a bigger battery.

The Pixel 4 is powered by a 2800mAh cell (the Google Pixel 3, for comparison, contains a 2900mAh cell − one that we described as “paltry” a year back). What’s more, the 90Hz refresh rate demands a lot of power.

You therefore might not be shocked to hear that that Pixel 4’s biggest shortcoming is its stamina. Here’s what we wrote in our review:

“2800mAh is a fairly small capacity, even for a phone this size. This, plus the added power drain a high refresh rate requires, means it’s all too easy to drain the Pixel 4 of its charge with a day of moderately heavy use … the Pixel 4’s battery life is without a doubt shorter than most competing flagships.”

For all of the battery life daredevils out there reading this, there is a way to lock the Pixel 4 display’s refresh rate to 90Hz, regardless of screen brightness levels.

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First, you need to unlock Developer Options. To do this, go to Settings > System > About Phone. Then tap the Build Number button seven times.

To lock the Pixel 4’s display refresh rate to 90Hz, go to Settings > System > Developer Options, and select ‘Force 90Hz refresh rate’.

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