Installfest PXE Server
BIOS settings to change on Dell Precision 5510/5520: (incomplete instructions)
When you boot up your computer, repeatedly press F2 to get into the BIOS menu. In general > boot options, switch from UEFI to legacy boot. In another section in the general tab, enable the Legacy OPRom setting. OPRom stands for option rom and allows specific modules for the legacy mode to be run, for example, low level USB and networking drivers among others which will allow the PXE server to boot. In the Secure Boot menu, disable secure boot. Finally, enable USB wake (not sure if this affects whether the PXE works or not) in power management or similar tab and enable thunderbolt commands preboot (the ethernet dongle uses thunderbolt port) and set security to none. You can change this later. Then click save, check "save as custom settings" if you want to revert to your old settings later, then reboot.
When you boot up your computer the next time, repeatedly press F12 to get into the boot menu. Under legacy, choose the "Network PXE" option (not the ipv4 option below it). You should see bigger text pop up than what was in the boot menu (in a pixelated font) then the PXE image will load. (It should say something like "Network boot from... Copyright Intel inc... CLIENT MAC ADDR" etc.) Basically at 10:44 in this video detailing PXE (don't worry about FOG, it is just the PXE boot menu that has been loaded).