This is quite a simple one. I have two questions; how much power will be required by the specifications listed below (bearing in mind limited future expansion such as graphics card) and which brand of PSU is known to be more reliable and/or safe (which, in my books, also indicates general quality)?
Processor: AMD Phenom II X4 965 3.4GHz Black Edition. Graphics card: XFX HD 5770 XXX 875Mhz 1GB GDDR5. Drives: 1 DVD RW, 1 SATA 7200rpm HD. Other power drains: 2 USB HD's, Antec 300 with 3 extra case fans.
PCI Express® based PC is required with one X16 lane graphics slot available on the motherboard
450 Watt or greater power supply with one 75W 6-pin PCI Express® power connectors recommended (600 Watt and two 6-pin connectors for ATI CrossFireX™ technology in dual mode)
Certified power supplies are recommended. Refer to http://ati.amd.com/certifiedPSU for a list of Certified products
Minimum 1GB of system memory
Installation software requires CD-ROM drive
DVD playback requires DVD drive
Blu-ray™ playback requires Blu-ray drive
For an ATI CrossFireX™ system, a second ATI Radeon™ HD 5770 graphics card, an ATI CrossFireX Ready motherboard and one ATI CrossFireX Bridge Interconnect cable per graphics card (included) are required
Here are the official ATI recommended power supply requirements for the ATI Radeon HD 5770 and 5750 video cards:
450 watt or greater power supply with one 75 watt, 6-pin PCI Express® power connector recommended.
600 watt or greater power supply with two 75 watt, 6-pin PCI Express® connectors for ATI CrossFireX™ technology in dual mode.
The recommendations are for an entire pc system.
Corsair and Seasonic are two of the brands that have a reputation for high quality power supplies that consistently earn high marks in technical reviews. They are reliable, stable, and come with a 5 year warranty. Some of the newer models come with a 7 year warranty. Lately we've been seeing a few other brands offering some high quality units.
I'll pick out a 650W from those lists. I tried to size it using the link you gave my but it came to too low a wattage (300). The graphics card that I have chosen requires 450W, so I'm not sure how it came to the conclusion of only 300W. I'm a bit of a future-proofer so 650W is enough for future mods.