I disabled CSM in my ASRock motherboard's BIOS because a game required Secure Boot. After restarting, the computer now skips the ASRock startup screen and goes directly to Windows. I can no longer see or enter the BIOS, even after clearing CMOS by removing the battery. I also tried entering UEFI Firmware Settings through Windows, but the display remains black. The system uses a Sapphire RX 580, and neither HDMI nor DisplayPort shows the BIOS screen. How can I regain access and enable Secure Boot?
3 Answers
Try entering the firmware from Windows by holding Shift while selecting Restart, then choose Troubleshoot > Advanced options > UEFI Firmware Settings > Restart. If the computer restarts to a black screen, the issue is probably that the graphics card is not displaying the motherboard’s UEFI screen with CSM disabled.
The RX 580’s vBIOS is worth checking, but only use the exact firmware and flashing utility provided for that specific Sapphire model. If it is already up to date, flashing it again probably will not help. Testing with a different monitor connection, another display, or a newer GPU is safer before attempting a firmware flash.
Make sure the CMOS reset was performed exactly as described in the motherboard manual: shut the PC down, disconnect power, use the clear-CMOS jumper if available, and then restore the default settings. If you still get Windows but no firmware display, connect the monitor to the motherboard’s video output if the CPU has integrated graphics, or temporarily try another graphics card. Some older cards need a UEFI-compatible GOP firmware to show an image with CSM disabled.
I checked the RX 580 firmware and it already appears to be the latest version, but HDMI and DisplayPort still give no image during startup.