T590 Power up issue

(Sorry for any typos. Obviously am having to type this on my phone like a goddam animal...)

Apologies if troubleshooting questions aren’t allowed, I’m just super stressed and the Lenovo phone support is closed for the evening =\

Any help is much appreciated!

Tl;dr: Does not power up (blank screen, power button not lit up) but fan runs very loud. What do?

So I’m doing regular stuff* on my laptop this afternoon, nothing crazy RAM hungry or anything, and it powers off. Blank screen but with the fan running super loud.

I force a shut down (holding down the power button). When I try to turn it on again I just get the blank screen and loud fan.

Stuff I’ve tried that hasn’t worked: Unplugging the AC (runs same off the battery) Plugging in the AC (power button flashes 3 times and light by AC socket comes on, as per usual) - Pressing the emergency reset hole button - Holding down the power button for 60 seconds - Connecting to an external monitor (no signal) - Pressing caps lock button to see if the light comes on (it doesn’t) - Checking if there is any faint light coming from the screen (no, and I stubbed my toe in the dark)

Any ideas? =|

I have had a couple of incidences this past week where it doesn’t get into sleep mode properly. Specifically, when I’ve been watching a video full screen, I pause it and wander off for a while - it should be sleeping when I come back but instead it freezes on a blank screen and I have to press the power button to force it into sleep mode and then press again wake it up. Might be related?

I’m worried it’s something serious to do with BIOS. When I first got the laptop (16 months ago) I had an issue with the battery not charging and I had to reinstall the BIOS drivers. Nerve wracking.

I’m probably not going to take it apart. If anything physical needs doing to it then I’ll send it away (this damn thing is worth more than I am).

* If relevant: I had some browser windows and some text files open. I was running a full scan with Windows antivirus or whatever it’s called. I was plugged into a TV as a second monitor - first time I’ve used it for an extended period of time and I was messing with the display settings on my laptop earlier in the day but I don’t see what I might have done wrong.