laptop shuts down randomly

[apoorv569]

my laptop (hp 430) shuts down randomly with this weird screen -View: https://imgur.com/U9gHKVM. sometimes its like this sometimes only white color sometimes red sometimes static noise and restarts with a error system temperature 90D, sometimes it restarts normally no error also when i touch the bottom of laptop it does not feels even warm also the air coming from fan vent is not even warm it just thinks its overheating, this happens with Linux only windows works fine(it happened in windows also but rarely). also when i plug the charger it happens almost immediately without the charger it takes sometimes to happen 1-10 mins doing absolutly nothing.
i have tried installing power management tools like tlp, cpufreq, psensor to monitor temps. tried updating drivers, tried updating kernel, tried different distros, tried changing ram tried changing hdd got my laptop fully disassembled and clean, changed thermal paste, went to a repair shop for total diagnostics, nothing helped.

[PlasticTrees]

Could be power supply overheating. Could you probe the PSU?

[apoorv569]

40 minutes ago, PlasticTrees said:

Could be power supply overheating. Could you probe the PSU?

but it happens without the charger also when its running on battery.

[PlasticTrees]

2 minutes ago, apoorv569 said:

but it happens without the charger also when its running on battery.

Yes, but you said it occurs almost instantly after plugging it in and 1-10 mins without. The PSU will be receiving more power therefore will produce more heat when charging.

[apoorv569]

1 hour ago, PlasticTrees said:

Yes, but you said it occurs almost instantly after plugging it in and 1-10 mins without. The PSU will be receiving more power therefore will produce more heat when charging.

i check the output of psu with multimeter, according to the psu specifications output should be 18.5v and multimeter showed 14.9v. is it ok?

[apoorv569]

On 4/14/2019 at 8:43 PM, apoorv569 said:

i check the output of psu with multimeter, according to the psu specifications output should be 18.5v and multimeter showed 14.9v. is it ok?

i got the psu repaired and this problem is still there nothing helped so far.. plz help