![Dallas Warren on Twitter: "Attempting to use external monitor with laptop (Dell M4800). Fn+F8 shows "No External Display", finally found ref "disable Optimus in BIOS", after disappearing down rabbit hole with others. Dallas Warren on Twitter: "Attempting to use external monitor with laptop (Dell M4800). Fn+F8 shows "No External Display", finally found ref "disable Optimus in BIOS", after disappearing down rabbit hole with others.](https://pbs.twimg.com/media/Dibmb5xUEAAxfom.jpg:large)
Dallas Warren on Twitter: "Attempting to use external monitor with laptop (Dell M4800). Fn+F8 shows "No External Display", finally found ref "disable Optimus in BIOS", after disappearing down rabbit hole with others.
![External Display Feature on Precision M4800 with E-Port/E-Port Plus Docking Solution | Dell Kiribati External Display Feature on Precision M4800 with E-Port/E-Port Plus Docking Solution | Dell Kiribati](https://supportkb.dell.com/img/ka02R000000i1WfQAI/ka02R000000i1WfQAI_en_US_1.jpeg)
External Display Feature on Precision M4800 with E-Port/E-Port Plus Docking Solution | Dell Kiribati
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