Yes - this should be fine for just about anything you want to play. I would suggest a solid Tier 1 power supply and possibly going to 600W. Honestly you want a good strong 12V rail but a Tier 1 over 600W will do a solid job.
Also, do some research on the memory you wish to use. Use the fastest your MB can handle and ensure you get a good solid brand. Quality is important here too.
Both memory and power supply questions can be researched on Toms.
A good 500W power supply is easily enough.