Legacy Video Graphics Array (VGA) adapters often lack the necessary compatibility for the Unified Extensible Firmware Interface (UEFI), a modern system firmware that replaces the traditional Basic Input/Output System (BIOS). This incompatibility stems from UEFI’s reliance on graphics output protocols not present in older VGA hardware, specifically the Graphics Output Protocol (GOP). A system with UEFI firmware will typically fail to initialize the display when a non-compatible VGA card is installed, resulting in a blank screen during startup.
The shift from BIOS to UEFI brought improvements in security, boot speed, and support for larger storage devices. However, this transition created a compatibility gap with older hardware, including VGA cards. While VGA cards functioned adequately under BIOS, their lack of UEFI support renders them unusable in many modern systems. Understanding this incompatibility is crucial for troubleshooting boot issues and ensuring appropriate hardware selection for UEFI-based systems. This limitation highlights the importance of verifying hardware compatibility before upgrading or building a new computer. Successfully booting a system requires a graphics adapter that adheres to UEFI specifications.