Problems That Allow REPB/Block CSM
Problems That Allow REPB/Block CSM
Today I tried turning on the resizable bar and experienced some FPS improvements—it worked partially. The main problem is: once I turn off CSM, I can’t see my BIOS. I can still boot into Windows normally. Here’s what I did step by step:
- Updated MOBO BIOS (version F33j)
- Installed GPU VBIOS
- Updated Nvidia drivers (version 466.27)
- Changed Windows boot from MBR to GPT
- Used MSInfo32 to verify BIOS mode is UEFI
- Disabled CSM support in BIOS
- Enabled ReBAR with 4G decoding ON
- Saved BIOS, restarted into Windows
- Confirmed ReBAR in Nvidia Control Panel
- Rebooted back into BIOS (MOBO shows Ab, code for BIOS)
Now my display doesn’t show anything even though I’m in BIOS. Pressing escape + enter and rebooting without resetting CMOS still works.
Other attempts included:
- Using different HDMI cables
- Forcing Windows to UEFI via Recovery Mode
- Clearing CMOS and disabling CSM only
- Flashbacking to an older BIOS version
- Checking PCIe display output in BIOS when CSM is off
- Hot-swapping HDMI while in BIOS
- Using different HDMI ports on the GPU
I read that some users faced issues with CSM when using DisplayPort or silent BIOS on their GPU. But for me, it’s not related because I’m using HDMI and my card supports a single BIOS.
If everything else fails, I’m stuck. Could be something I’m missing. Please help!