HP Ultraslim PC 8200 external power supply issue

[Discreto]

My external power supply for Ultra Slim 8200 stopped working. Once connected to the PC and PC start button hit 4 beeps are heard. There is 19.4 V DC on power supply output. One capacitor 104J100 seemed to be damaged (black spot in it). The capacitor replaced with slightly higher value ( 0.2 uF, 250 V) to no avail. Still 4 beeps. All components inside the power supply seem like brand new/no damage seen.

How to trouble shoot the issue?

Thank You for the feedback.

[DGroves]

the power supply brick is not worth fixing when replacements can be had for 10-20 dollars

the power supply needs to be 19.5 volts DC 7.4x5.0 mm  jack,  at  135 watts  minimum for a low spec system and 230 watts if using a highend cpu with max ram/storage drives/video

135 watt

https://www.ebay.com/itm/354936709025

230 watt

https://www.ebay.com/itm/156612758655?_skw=hp+230+watt+19.5++adapter&itmmeta=01JXETNYE21P5P1JX683KC3...

however if it's a learning experience you want, then google  "repairing switching power supplies"