Coolermaster is not a good brand. Look for Antec, Corsair, OCZ, NZXT, PC power and cooling, Seasonic, Silverstone, or XFX for power supplies.
The CPU is compatible with your motherboard according to HP.
The motherboard has a PCIe x16 slot, but you may want to be cautious as HP has been picky in the past about what GPU would work on it. Also no where do I see if it is PCIe 1.1 or 1.0. If it is 1.1 it will work with your GPU, but 1.0 it will not.
curious as to where you see that?Hp says The pci-e slot is v1.0