19 Amps...it may run it, but it's going to be struggling, a lot...
Do you want the PSU to be future proof? If not, then would work for now:http://www.newegg.com/Product/Product.aspx?Item=N82E16817153052
When do you think you will be upgrading again? I would suggest going with a future-proof PSU just so you don't have to upgrade it again.
The vx450 will handle your PC very nicely. The hx520/620 are just more future-proof, so that decision goes back to you.