Question My computer turns on but the fans only spin for half a second before everything turns off

AspectSaber

Commendable
Oct 2, 2021
82
3
1,545
So I was doing a power supply change to my PC due to the old one being loud and old, but during the process I must have done something wrong because now the computer does not turn on at all. The fans ramp up for half a second before they stop and the power button led doesnt even turn on. If you try to turn it on again, nothing happens this time, not even the fans spin for half a second anymore. What did I do? Is there a way to fix it?
 

AspectSaber

Commendable
Oct 2, 2021
82
3
1,545
full system spec? include brand and model of the psu
It's an HP modded office computer with the following specs:
Intel Core i3 7100
GT 1030 2GB GDDR5
8 GB DDR4 2666 (Single stick)
Some 180 watt HP power supply

The PSU I upgraded to is a 500 Watt thermaltake: Thermaltake Smart 500W 80+ White Certified PSU, Continuous Power with 120mm Ultra Quiet Cooling Fan, ATX 12V V2.3/EPS 12V Active PFC Power Supply PS-SPD-0500NPCWUS-W https://a.co/d/7bkp6IV
 

AspectSaber

Commendable
Oct 2, 2021
82
3
1,545
don't they have proprietary psu connection
No this one was surprisingly fairly standard. Also I'm so sorry i didn't say this but it was working fine for 2 weeks, but I decided to return the power supply to get a better one for the same price. Right now I swapped back to the one that came with it and that's where the problems started