|The HP specs for your model show you have a standard ATX case, which is good. There are many versions of the ATX standard that reflect the changes in hardware over the years. That said, the power supply I linked is compatible with your HP.|
The cable bundles vary somewhat from model to model. usually the difference is in the number of connectors. Power supplies come as powerful as 1200W. That power supply will have more connectors because it is assumed you need more, or you wouldn't need a 1200W PSU.
You will find there may be surplus cables. Some connectors can be separated or combined to form a larger connector. For instance the main power connector on your motherboard is most likely a 24 pin connector. The linked power supply has a 20 pin + 4 pin that slip together to form the 24 pin. That is done to make that PSU more flexible when used in older 20 pin systems. Just tie up any surplus cabling to keep it out of the fans and the airstream.
I doubt you will have any problems but if you do, you know where to find us.
You do need to take precautions with electrostatic discharge. Computer components can be damaged by static charges on your body. Just touch the metal case before unplugging the computer and you should be fine.
One more word of warning. If you decide to clean inside the case, DO NOT use a vacuum cleaner. Static again. Best to use compressed air to blow out the dirt/dust. Office supply and computer shops sell canned compressed air for that use.
Newegg.com is a very reputable online store. You can print the rebate form off their site.
See the guide at the link below.