Insufficient space in Option ROM BIOS

What is ROM-SPACE-EXHAUSTED?

ROM-SPACE-EXHAUSTED shows up as a medium-severity hardware BIOS/UEFI fault. The board has too many associated devices with custom ROMs (eg RAID controllers, multiple GPUs) and has run out of space to initialize them (POST). Another common trigger is active Legacy and CSM boot modes. Follow the steps below to fix it.

Common Causes

• Too many PCIe expansion cards plugged in
• Old board architecture with small ROM for BIOS
• Active Legacy and CSM boot modes

Step-by-Step Fix Guide

• 1
  Turn off CSM (Compatibility Support Module) and go to pure UEFI

  Turn off CSM (Compatibility Support Module) and go to pure UEFI is the first thing worth trying, since it resolves ROM-SPACE-EXHAUSTED for most affected systems.

• 2
  Disable unused integrated components (COM ports, internal SATA RAID)

  In case symptoms recur, the rest of the sequence deals with the less common side of bios instability.

• 3
  Disconnect unnecessary expansion cards

  "Disconnect unnecessary expansion cards" targets too many PCIe expansion cards plugged in, one of the documented causes of ROM-SPACE-EXHAUSTED.

Commands & Diagnostics

Frequently Asked Questions