Question Power light and fan function, but no other sign of life. Will replacing motherboard be likely to fix it?

[halfbeing]

My Lenovo Yoga 710-14IKB now shows no sign of life except for the power light and fan. I've tried to power it up both with and without an external monitor, and I've tried powering on using the OneKey button to go straight to BIOS, but that makes no difference. When I plug my phone into it I get a message about not being correctly connected to the USB port. I have to force a shutdown to turn it off.

Recently, the laptop was possibly showing signs of trouble with the graphics or the screen. I would sometimes find my screen flashing. This was often associated with particular scroll positions on particular websites. After a bout of flashing, the screen would often shimmer for a while. This only happened on the laptop screen, never on the external monitor. Sometimes, when I powered on, the external monitor would start working, but not the laptop screen. I had to unplug the external monitor to get the laptop screen working again.

My guess is that something on the motherboard has stopped working. Would that be likely to be a correct diagnosis? If so, would buying a replacement motherboard on eBay be likely to get the computer working again for long enough to make it worth doing, or would I be setting myself up for other problems by doing so?

 

[halfbeing]

I have found the problem, and it was not a motherboard component as such. It was the wireless card and/or its socket. My wireless card every now and then shifts a minute amount and starts to cause problems. Previously these have only been blue screens after booting or waking from sleep, and/or complete loss of wireless functionality. When that happens, I have to open the computer up, nudge it a little, and it starts working again. I did that just now, and the computer started working again.