Question HP Compaq SFF different case better PSU and GTX 970

[babymight]

Hey there,
I have a HP Compaq 8300 Elite SFF, and was wondering if it would be possible to take the motherboard out, place it in a bigger case, get a better PSU, and use a 970?
If I can do this, any links to cheap cases, and power supplies would be appreciated as I am not great at this PC building

 

[Barty1884]

Do you have a specific model of Compaq?

For example, the 8200 Compaq SFF uses a non-standard MB, and proprietary PSU connectors so transplanting is somewhere between difficult & impossible.