Got into internet Recovery Mode but black screen in the half way

It's always not a good day when the computer is down...

iMac of 2015-2017 (can't remember which year), system updated 2022, and did receive a pop-up message saying something like my iMac specs were unable to support the latest version. And this morning, the screen suddenly turns black, but it is not shut down (the USB fan is still on, and will only go off if the computer is shut down).

I have tried:

*unplugged all accessories and restarted a few times, but the screen always goes black when the progress bar reaches 1/3

*command plus R button, the Apple logo shows up then the screen goes into black again for hours without anything on it.

*option+command+R button, Globe icon appears, successfully connected to wi-fi, the progress bar appears, but the screen goes into black again when the progress bar reaches 1/3, and it has been hours in black screen without any changes.

Besides sending my iMac to the store, I am hoping to hear some other useful methods that might help me to solve this problem.

Thank you.