Solved: Precision M4800 : Input lag at log in, Switchable graphics not functioning, GPU fan "chirping" when ... - Page 5 - Dell Community
![Amazon.com: Dell M4800 15.6in FHD Ultrapowerful Mobile Workstation Business Laptop Computer, Intel Core i7-4900MQ 3.8GHz, 16GB RAM, 500GB HDD, WiFi AC, NVIDIA Quadro K2100M, Windows 10 Pro (Renewed) : Electronics Amazon.com: Dell M4800 15.6in FHD Ultrapowerful Mobile Workstation Business Laptop Computer, Intel Core i7-4900MQ 3.8GHz, 16GB RAM, 500GB HDD, WiFi AC, NVIDIA Quadro K2100M, Windows 10 Pro (Renewed) : Electronics](https://images-na.ssl-images-amazon.com/images/I/61SbokaX8hS._AC_UL420_SR420,420_.jpg)
Amazon.com: Dell M4800 15.6in FHD Ultrapowerful Mobile Workstation Business Laptop Computer, Intel Core i7-4900MQ 3.8GHz, 16GB RAM, 500GB HDD, WiFi AC, NVIDIA Quadro K2100M, Windows 10 Pro (Renewed) : Electronics
![Amazon.com: Dell M4800 15.6in FHD Ultrapowerful Mobile Workstation Business Laptop Computer, Intel Core i7-4900MQ 3.8GHz, 16GB RAM, 500GB HDD, WiFi AC, NVIDIA Quadro K2100M, Windows 10 Pro (Renewed) : Electronics Amazon.com: Dell M4800 15.6in FHD Ultrapowerful Mobile Workstation Business Laptop Computer, Intel Core i7-4900MQ 3.8GHz, 16GB RAM, 500GB HDD, WiFi AC, NVIDIA Quadro K2100M, Windows 10 Pro (Renewed) : Electronics](https://m.media-amazon.com/images/I/41dPzXGueFL._AC_UF894,1000_QL80_.jpg)
Amazon.com: Dell M4800 15.6in FHD Ultrapowerful Mobile Workstation Business Laptop Computer, Intel Core i7-4900MQ 3.8GHz, 16GB RAM, 500GB HDD, WiFi AC, NVIDIA Quadro K2100M, Windows 10 Pro (Renewed) : Electronics
![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.
![Amazon.com: LeFix Replacement for CMOS RTC BIOS Battery Dell Precision M6600 M4600 M4700 M6700 M4800 M6800 M3800 15 (7510) | Inspiron 15 (7559), 15 (7577), 9400, 9300, 9200 | Chromebook 13 (7310)|XPS 1820 : Electronics Amazon.com: LeFix Replacement for CMOS RTC BIOS Battery Dell Precision M6600 M4600 M4700 M6700 M4800 M6800 M3800 15 (7510) | Inspiron 15 (7559), 15 (7577), 9400, 9300, 9200 | Chromebook 13 (7310)|XPS 1820 : Electronics](https://m.media-amazon.com/images/I/61z1-dtbZvL._AC_UF894,1000_QL80_.jpg)
Amazon.com: LeFix Replacement for CMOS RTC BIOS Battery Dell Precision M6600 M4600 M4700 M6700 M4800 M6800 M3800 15 (7510) | Inspiron 15 (7559), 15 (7577), 9400, 9300, 9200 | Chromebook 13 (7310)|XPS 1820 : Electronics
![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)