MPC 2000XL - Blank screen, all lights are on. Checked

I've bought a MPC 2000XL second hand. Attic find; not used in a while.
Screen didn't work. I expected it to be a matter of replacing it since the rest looked unused. Optically in perfect shape.

I replaced the screen but the issue remains: It blanks, all other lights are on.
I tested:
- all cables / wires / ribbons
- RAM
- Floppy drive

So what is left to test? It seems like it's just stuck.
I want to install an SD drive but to do that I need to use the 1.20 OS floppy to upgrade, and atm it doesn't do anything...

I mainly need to know what part to replace?
The PSU?

SKRD wrote:So what is left to test? It seems like it's just stuck.

If the screen was bad, then you'd at least be cable to press a button such as play, record, 16 levels to see if anything lights up.

Replacing the screen wasn't the smart thing to do due to the cost.

The issue is with the mainboard itself but it can be diagnosed from an internet forum as there are multiple components on the mainboard that could be at fault.

In another thread you made, you wondered about what PCB - they're talking about the mainboard.

Does your unit have the 8 out as well? If so, unplug the ribbon connector going from the 8 out to the mainboard and see if your unit turns on.

Yeah; I'm trying to narrow it down with a multimeter... Must be the PCB indeed.

What about the questions I asked you? Any ideas?