The GPU or what is pushing the external now has more work to do.
i own a laptop with a rather small screen so i wanted to upgrade to a bigger monitor. when i plugged my monitor into my laptop and launched up a game i had major fps drop. a game i always get an easy 100+ fps on i was barley getting 30. both the laptop and the monitor are 1920x1080. i had no fps cap and vsync was off.
monitor: https://www.bestbuy.com/site/asus-24-led-fhd-freesync-monitor-black/5591926.p?skuId=5591926
laptop: https://www.acer.com/ac/en/US/content/model/NH.Q3ZAA.001

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