I would suggest an Antec 430W, or 550W Trueblue power supply. I have had mine for the past year without issue and it has a great reserve power they do not tell you about, plus that cool blue is a great color. The power supply is critical to the sytem as it maintaines the power needed to obtain the speeds, drives, CD-ROMS etc that you would use daily on your machine.
As stated above, do not risk your system and $1000 on a wimpy generic PSU or you will waste all your other components and nothing will work.
Round cables allow more air flow through your box, greatly reducing your system temp and not to mention how cool they look if you have a box with a plexi window.
For a great stable board at only $92, you might consider the Albatron KX18D PRO II. It also allows for very easy overclocking should you ever want to try that out in the future.
Also, do not put your processor and mobo together without Article Silver 5. Do not use that stuff that comes in the mobo box, it has an extremely low rating and will not cool your processor very well. The AS 5 compond is put between the processor chip and the heatsink. Check their web site
http://www.articlesilver.com for a complete tutorial on how to apply the compond to your CPU properly. Comes with photos so you can visually see what to do.
Hope this helps.
Cheers.