HP laptop doesn't power up

I had to give back the another charger, and suddenly, now it powers up with its own charger. Still can't repower after turning it off. I am puzzled...

Run a Startup Repair from disk to check over the boot files.

Reset the BIOS to defaults, taking note first of the SATA controller setting. Set also the hard drive as first device to boot.

Still no luck with two another chargers..

Can you take it to a shop such as I described to ask them to plug it into their universal charger. Then you'll know for sure that's the problem. They may have a charger to sell you or you can then use the specs they give you, or which you find doing a search for your model laptop + replacement charger, to shop online.

I did with universal and specific as well...

If the charger will not work, with or without the battery, after draining residual power by holding the power button down for 30 seconds, then your mobo may have failed. Is the fan spinning or is there any other signs of life?

As I also said earlier, at our Geek Squad they will run a free mobo and hard drive test to confirm those. Can a shop there do this for you?

I have checked the hard drive manually and it has no problem at all (however, I am trying to power on without it).
As I wrote, I have already ordered a new mobo and it did not work with that also, behaved like before.

How about the power port connection?