Question Lenovo ideapad 100-15iby wont start

Aug 2, 2019
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Hello I have problem with said laptop, the laptop powers on for few sec but I dont hear a hdd booting only the optical drive starts giving any nosies but it dies after few seconds, also a sec before computer shuts down I can see the screen going on but right after it goes off and power led starts blinking.
I tried doing hard reset, disconnecting battery and AC charger, hold the power button for 15-30sec conect the battery and ac charger but this doesnt help. Tried taking everything out and swaping the harware that I was able to do for example ram but that wasnt the problem, I dont have mutimeter to check whether there is a shortage on the mobo which might be causing this.
Also i have tried resetting the CMOS by removing the battery firstly for 30sec but failed so i took it out for another 15-30 min to make sure it resets properly also while the cmos battery was out I done another hard reset to drain the power for the laptop.

I am really lost with this, I tried everything that I knew might help boot the laptop but google failed with giving more help and thats why I asking you all for help to bring back the laptop to life after long time.

Sorry if something doesnt make perfect sense but English is not my first language, hope you forgive me :)