The hated F12 at boot… Remove this with PXE booting:
Windows Deployment Services requires network boot clients to press F12 before entering the Windows Preinstallation Environment (WinPE) deployment environment. To remove the requirement to press F12:

1.Right-click the Windows Deployment Services server in the Microsoft Management Console (MMC) Windows Deployment Services Management snap-in and select Properties.
2.Select the Boot tab.
3.For the architecture required, click the Browse button and select the “.n12” version of the boot ROM, as the figure shows. For example, instead of, select pxeboot.n12
4.Click OK.