Nexus 5x turning off due to overheat - even after factory reset

Hi,

I have used my Nexus 5x without many problems until 2 days ago when it started having serious overheating problems. It normally overheats more than other phones, but this time it is getting up to 119F (from GSam Battery Monitor) and then turning off itself. Battery drains from 100% to 0% in about 1-2 hours without using any app and in airplane mode.

I tried all the tricks I found in posts to identify a misbehaving app but without any success. I finally decided to do a factory reset which improved a little but not that much: I can use it for 5-10min then it overheats and turns off.
This would point to a hardware failure so I already ordered a new battery. The strange thing is that when it is in Recovery Mode (power+down) it doesn't overheat nor drains the battery. I.e: Hardware seems to work fine when there is no OS running. So I don't have much expectations that the new battery will fix it.

Do you have any idea what else can be done? Any recommendations?

Thanks you all,

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