Although KBE (WinPE 3.0) contains a vast number of Windows 7 NIC and mass storage drivers, there are new computer models being released all the time containing chipsets that were not available when WinPE 3 was released. We are supplying our customers with a KBE Driver Pack that we will be continually updating as we find new drivers. These drivers include the Dell WinPE drivers (version A08), as well as kace drivers for atheros, realtek, startech 7500 usb to ethernet dongle, usb3, vmware and yukon chipsets.
If just looking for the Intel e1c drivers for Dell models such as the Optiplex 790 and 990, you can download just those, add them to the appropriate KBE_windows_xXX folder, recache and create a new KBE.
Use USB 3 drivers to add to your KBE if trying to use a USB 3 port for the Startech 7500 usb to ethernet adapter or for USB KBEs.