Question Getting back into BIOS on Asus Z97M-Pro after CMOS reset

[incansvl]

I have a machine built around an Asus Z97M-Pro motherboard and i7 4770K cpu that has been running reliably for years.

About a year ago I had to replace the CMOS battery, and after the CMOS reset I had trouble getting into the BIOS. The machine would boot to the "Type <del> to enter setup" prompt, but it was ignoring any USB keyboard plugged into it, so I couldn't actually type <del>!

In the end I dug up an old PS/2 keyboard, and that finally let me enter the <del> key to get back into the BIOS.

A week ago I hit another problem (no video output, black screen). I ended up doing another CMOS reset to get video output from the onboard graphics. However I am stuck again at the dreaded "Type <del> to enter setup" prompt, and this time it's ignoring both USB keyboards and PS/2 devices.

Has anyone hit this same problem with and Asus Z97 motherboard, and found away around it?

 

[Lutfij]

Welcome to the forums, newcomer!

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

Just an FYI, you don't type DEL, you tap/hit the DEL key on the keyboard.

 

[incansvl]

Welcome to the forums, newcomer!

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

Just an FYI, you don't type DEL, you tap/hit the DEL key on the keyboard.

In this case, as the system is (or was) (a) long-term stable; and (b) not getting beyond the BIOS splash screen, the gruesome detail of the config seems less relevant, but I can provide most of this.

An exception is the BIOS version, because at the moment I can't get into the BIOS to check the version!

I am also aware of the need to repeatedly hit the del key to get into the BIOS, i'm not just pressing <del> once.

System Specs
CPU: i7 4770K (was running overclocked to 4GHz, but the BIOS reset will have set this back to default, 3.5GHz)
CPU cooler: Zalman CNSPX11
Motherboard: Asus Z97M-Pro
Ram: 16GB HyperX DDR3
SSD/HDD: 1TB Crucial M.2 SSD + 2TB 2.5" WD HDD
GPU: Gigabyte Radeon 6700XT (removed while investigating black screen fault)
PSU: Antec 520W High Current Gamer
Chassis: CoolerMaster uATX (model no. long forgotten)
OS: Windows 10 Pro 64 bit
Monitor: Dell S3220DGF

 

[incansvl]

I have a machine built around an Asus Z97M-Pro motherboard and i7 4770K cpu that has been running reliably for years.

About a year ago I had to replace the CMOS battery, and after the CMOS reset I had trouble getting into the BIOS. The machine would boot to the "Type <del> to enter setup" prompt, but it was ignoring any USB keyboard plugged into it, so I couldn't actually type <del>!

In the end I dug up an old PS/2 keyboard, and that finally let me enter the <del> key to get back into the BIOS.

A week ago I hit another problem (no video output, black screen). I ended up doing another CMOS reset to get video output from the onboard graphics. However I am stuck again at the dreaded "Type <del> to enter setup" prompt, and this time it's ignoring both USB keyboards and PS/2 devices.

Has anyone hit this same problem with and Asus Z97 motherboard, and found away around it?

I finally got back into the BIOS! Posting the solution here in case it helps anyone else with the same problem.

I found a posting somewhere (Reddit?) from someone who had a different Asus Z97 motherboard to mine, but the same issue getting into the BIOS. They found the solution was to disconnect all the external connections (disks, USB etc.) except the bare minimum, and go down to one stick of RAM.

That seemed a bit extreme to me, so tried a "halfway house", disconnecting the SATA drives but leaving my NVME boot drive and the other peripherals connected, and the full complement of RAM.

Voila! the board responds to a (USB) keyboard, and I can access the BIOS!

It seems for some crazy reason the board doesn't like having any SATA devices connected directly after a CMOS reset, and will ignore keyboard input at the "hit <del> to enter BIOS" prompt.