Since that time, the female power receptacle on it has broken twice. I've had this EXACT (Model 20266) Lenovo laptop since 2014. Thanks to Power Jack Repair I figured out how the loose power receptacle on my Lenovo 20266 laptop is related to this Lenovo no response power issue. Advice on remediation would also be appreciated there's no insurance on the machine, so if someone knows an easy fix I'd love to hear it, but if not I will bite the bullet and bring it to the local repair shop. I'm looking to see if anyone knows anything about this or has experience with this kind of issue, and can corroborate or dispel my suspicions that it's a battery problem. The only 'modification' I've made was configuring the BIOS to allow me to boot into Linux from USB, but that was about a week ago now with no trouble, and I was using the native Windows 8.1 on the SSD when the shutoff occurred. Machine is a Lenovo Yoga 2 Pro, all original hardware except the adapter. Needless to say, this latest development is unprecedented. Before that began, on a couple of occasions I've had the screen suddenly flicker and go dark without the machine shutting off, which has always been easily solvable by unplugging it and closing/opening the lid. Starting 1-2 days ago I began experiencing 'loose connection' problems with it, where it would only provide a charge when it was inserted at some angles (not that there's much wiggle room). It's probably worth noting that I've been using an off-brand replacement adapter, since the OEM one stopped working. No fan noise is ever evident, and the screen and keyboard remain entirely dark. The light then remains on unless the adapter is unplugged and the power button is held down (as you would do for a hard reset). If I press the adapter into the port with a bit of force, the power light comes on but the machine won't power up. When the adapter is plugged in I get an amber light that blinks occasionally and periodically. The current status is that I cannot power it on and the power button (as well as the button to boot to BIOS) do nothing.

My suspicion is that it's a battery or power problem. I don't expect that it did overheat: I wasn't actively monitoring the temperature, but I checked after it clicked off and it was relatively cool to the touch (and it's thin, so I would almost certainly feel severe overheating).

So I was watching some YouTube videos earlier and my computer suddenly shut off, similarly to what you would expect if it had overheated.

Lenovo yoga 720 keyboard not working