The motherboard in your computer is HP proprietary. It has a 4-pin power connector instead of a standard 24-pin ATX power connector. You will have to buy any PSU upgrade from HP. The problem is there is no good information on which PSU's will be compatible with your motherboard. However, I believe that the 400W (L69242-800) should be compatible: https://partsurfer.hp.com/Search.aspx?searchText=L69242-800
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