Intel has discontinued support for older Desktop Boards. If the drivers are not available on the main Intel website, follow the steps below.
E1 is a quirky code. It means all core drivers have loaded, and the board is waiting for user input (keypress or USB device enumeration) or stuck in a power management handshake. intel desktop board 21 b6 e1 e2 driver work
Some Intel Desktop Boards lack native NVMe driver support in BIOS. If an NVMe SSD triggers E2, either flash a modded BIOS with NVMe driver injection or use a SATA SSD instead. Intel has discontinued support for older Desktop Boards