Please suggest a proper PSU for the following configuration.

Get a good 650W bronze PSU. Pretty much anything other than cooler master.

Any quality PSU of 550W and up will be sufficient. Look at Seasonic, Corsair,PC P&C, Antec, Superflower for a start. Consider the XFX pro 550W

No probably not but that is not the right question to ask. There are several things to consider when you are deciding which is the best PSU for your build:

1. Future use - are you going to crossfire or SLI; are you going to overclock?
2. Efficiency - this will save you on electricity and cooling and an efficient PSU will be much more quiet
3. The quality of the PSU. Some PSUs put out current that fluctuates (they are not "stable"). This unsteady current can wear out components way before their normal life span. This is one of the most important considerations.

Your build will draw approximately 400W - 450W. The 3570K is a great card to overclock but you need a sufficient amount of headroom to overclock. Even if you are not going to overclock immediately, it does not cost you that much to size your PSU with enough power to do so.

All PSUs run most efficiently, coolly and quietly at 50% of their capacity. Thus if you wanted the most efficiency you would purchase an 800 - 850W PSU (which is overkill) and this is what I did for my computer which has one GPU. However a 650W PSU will also work well provided it is a quality PSU. My HX 850 runs so efficiently that I have never even heard the fan turn on which means it is running cool in my case and saving me money on electricity.

As you get into the 450-500W PSUs you often get into a myriad of low quality PSUs that only builders like Dell use because they are cheap. Some of them have actually exploded in cases but more often they are very unstable and are hard on your expensive components.

Therefore the best budget choice would be something like the Corsair CX 600. You could move up to the Corsair TX 650 for about $30. If you look for sales you can get smoking deals. I bought my Corsair HX 850 for $144.00 on sale which was a great deal.

Also it is best to buy a modular PSU if possible. This allows you to only install the PSU power cables that you need specifically for your build. The Corsair CX600 is around $70 and it does come in both a modular and non-modular setup for your cables.

If you are a riverboat gambler you might want to get a 500W PSU but if if fries your CPU you'll be sorry and you will have only saved $20 - $30.