Computer reboots on itself since I changed my GPU

[boolby92i]

Hi guys, I came from a long trip couple of weeks ago and came along with a new GPU Nvidia gtx 1050ti that I bought, when I got home I could not turn on my HP compaq elite8100, I was so excited to fix my new GPU after this I try to on my computer and it reboots on itself I thought this might be due to the psu but unfortunately the PSU that I bought was not designed for my mobo so I had to switch back to my older GPU but surprisingly the computer never stop fooling some time when I turn it on it last for over 4hours before it would go off some time it doesn't even allow the system to boot before it goes off I don't know what's going on

 

[hang-the-9]

Yes it can easily be your power supply, probably the most likely issue. If your motherboard has custom power connections, you may be able to find adapters for sale.