Cosmos laptop won't boot (black screen)

[luked34]

This might be a long shot, as the laptop is 6 years old now. I think it's based on a Clevo W650SH.

The blue light on the power button comes on, and after a few minutes the bottom of the laptop gets warm and the fan comes on. When the DVD drive is connected it makes noises as if it's trying to read a disk, and when a hard drive is connected it spins up. There are clearly signs of life but nothing shows on the screen or an external monitor.

I have tried all configurations using the two RAM modules and slots. The above happens with both modules plugged in. With one or none it switches on for a few seconds and off for a few seconds, then loops. Still nothing on the screen.

I have tried booting with a new CMOS battery, and with no battery at all.

From what I have read it may be a motherboard issue, but any ideas to try and revive it would be appreciated.

 

[Bastet]

This is a long shot but try disconnecting all peripherals, unplug the laptop, remove the battery, remove the CMOS battery & long press on the on/off button & leave things for 15 minutes then return the CMOS battery & reconnect everything then try starting up again.
You can try windows key + P to change projection mode to see if this does anything.
Otherwise the problem may be the Motherboard.

 

[luked34]

This is a long shot but try disconnecting all peripherals, unplug the laptop, remove the battery, remove the CMOS battery & long press on the on/off button & leave things for 15 minutes then return the CMOS battery & reconnect everything then try starting up again.
You can try windows key + P to change projection mode to see if this does anything.
Otherwise the problem may be the Motherboard.

No luck unfortunately, same result as before.

I've tried a few of the FN key combinations, e.g. sleep, change screen, change brightness. It doesn't seem to respond to anything but the power button.

Also the HDD LED flashes slowly. Does that indicate anything?