I got a lemon and I can't get a replacement and need to know who can help me

[GaWaPo]

This all in one PC has not worked since I brought it home from Costco in AUgust 2021. I worked through their concierge service. They could not fix it, so it was shipped back to HP. It came back and would not boot. It went  back again, due to slowness and noise, and it is going back for the third time today because it will not turn on. I have asked for a replacement. No one is willing to act on that or even refer me, saying it must be repaired. I am not going to call Customer support again. It has had the following things replaced: the mainboard, the fan, the HDD, and has had Windows reinstalled 3 times. I have spent hours and hours and hours on this! Can anybody out there tell me who to contact to get this mess resolved?  I have been without this system since late October when the issues became so unbearable it was shipped to HP. Since then it has not worked. SOmebody, help me!!!

[itsmyname]

@GaWaPo -- following things replaced: the mainboard, the fan, the HDD, and has had Windows reinstalled 3 times. 

Has the power-supply been replaced? 

Is the computer connected to a UPS (Uninterruptible Power Supply) to supply "smooth" electrical power, in case that your local electrical company is feeding "dirty" power into your location ?

Is the computer connected to a "power-bar"? Does the power-bar have "surge protection" ?

Have you tried a different power-bar (or UPS) ?

I think that you really need to contact HP Support, before the end of the 12-month warranty.