Black screen after 'Welcome to Grub'

Hello all,

I just tried to use my CNC router after not using it for a while and it won't boot.
When I first turned on the computer today, the CMOS had reset.

JW-D525M-GT motherboard (Atom D525).
LinuxCNC 2.6.7 installed on a USB stick.

BIOS is fine, then on screen appears 'Loading Grub', then "Welcome to GRUB!" then a black screen with no cursor.
The GRUB menu does not display and nothing further happens.

The LinuxCNC LiveCD on USB boots fine
I tried "boot-repair-disk-32bit" which did not help
Eventually after much trying I reinstalled LinuxCNC from USB to the same USB key.

And I got the exact same result.
I've now tried a different computer, and the LinuxCNC installed on the USB key booted fine, no issues at all.

Any thoughts?
The first thing I did was try nearly every different BIOS option without success.

John,

I thought of that. However it will boot and run a number of different Live distributions without problems.

From googling it seems a black screen at Grub can be a kernel nice switching issue (monitor resolution) though it would seem odd for this to suddenly occur. I'll try a different monitor when I next have a chance

When I first turned on the computer today, the CMOS had reset.

This means the battery went flat, replace it or it will happen again as soon as you leave it again for several days.

It is unlikely this is caused by anything else but BIOS settings reset, if this is all that occurred.

Look for some reference to 'Secure boot', that can do this if enabled. A lot of BIOSs
default to some sort of a UEFI boot setting.

regards

EDIT

I checked my Intel 525 board, the BIOS option for UEFI is the last item on the Boot section

Your board uses AMI BIOS, so don't know where it will be, but it will be there.

Whilst an incompatible monitor CAN cause this symptom, if it worked previously and all that has happened is that the CMOS battery went flat, it pretty much has to be a BIOS setting.
Check really throroughly, there may be a couple of options under UEFI, Secure Boot etc, they will all need disabling.

Well, I tried every single BIOS option. There are not UEFI / secure boot options in my BIOS.
I've replaced the CMOS battery.

I eventually got it to work by doing another new install, on to a different USB stick.

Working again. Frustrating to lose 6 or more hours to this though!

Well, I tried every single BIOS option. There are not UEFI / secure boot options in my BIOS.

That is strange, I have a very early 525 and mine has UEFI options.

At least you sorted it.