MSI GT72 sudden power off while gaming

How long have you had the unit?

 

5 years. No hardware issues until now, except an ssd died 2 years ago.

Starting to get annoyed with this, two days now, I spent a good hour running a game that usually instantly shuts down the laptop. Only difference is it was right after it was off the whole night.
Maybe some kind of charge building somewhere that dissipates during the night?

 

Try another AC adapter, if it fixes the issue then that is it.

 

Worth a try, just need to find one with enough power.
But if it's the adapter, why doesn't the laptop turn on when only on battery - while working fine if I disconnect adapter once it's already running?

 

AC mode requires a higher amount of watts and if AC adapter no longer produces that amount of power and when the system requested for the same amount of power then it will overload and shut off.

 

Yeah but on battery mode it doesn't even start

 

Well there ya go.....

The battery acts like a capacitor to supply extra when a high surge is needed and it also stabilizes voltage during most (if not all) times of operation.

Get out the fluke meter and make sure the battery is really dead (sounds like it is) and get ya one coming...amazon has always been a good battery hookup but make sure you check ALL the details before ordering (mwh, cell amount, size, reviews...you know).

 

You will also need to replace battery as N2ishun said. So do the battery replacement first, then see if you need to replace the AC adapter or not.

 

So anything other than 19.5V means it's dead?

Sure. Hopefully it's only the battery...

 

It's clearly the battery and here's the specs for your reference.

P/N: BTY-L77

Battery specs:
11.1V 7500mAh/83.25Wh