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Yes, the 2015 MacBook Air supports 4K displays at 60Hz | Ars Technica
Apple's early 2015 MacBook Air confirmed to support 60Hz 4K external displays | AppleInsider
2015 MacBook Air Can Drive 4K Displays at 60Hz - MacRumors
Resolution issues with external monitor. When I connect my MacBook 2017 (12 inch) with a HDMI to my new external monitor (Samsung M8), the text on the external monitor is so tiny
Yes, the 2015 MacBook Air supports 4K displays at 60Hz | Ars Technica
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