Dude 38A on the 12+ rail is plenty. I was just giving my contribution by sharing that at least my unit has worked perfectly well. Running an HD3870 + Overclocked CPU without problems. Price is perfect too.
You know, not all people can afford Corsair HX/TX or OCZ GameXStream series.
Dude...
Your psu has two rails, one with 15A and one with 16A, total 31A
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182044 - but hang on you cannot just add them up ok?
Under ATX design specifications, your 12V+2 rail is dedicated to the CPU, leaving only 15A for the rest of your system. You are grossly underpowerd using RD500 with your system, in fact i am suprised that you haven't run into trouble. But you may still have problems, as the HD3870 hasn't been out for 1.5 years, so we'll see shortly enough i would imagine. In the meantime, i would suggest taking note of your 12V rail stability, and the amount of hot air coming out of the PSU, as a rubbish unit like that under near-full load will eventually fail.
What I am saying is, who can afford to potentially lose their RAM and GPU and PSU if it fails - it is simply poor advice to suggest a Rosewill is good quality! My point stands - any PSU with 65% efficiency, no PFC etc is CRAP! Regardless of what
you can afford. Read the Multi/Single Rail PSU info in my sig if you want more information.
The OP's suggested PSU only has 20A for the rest of the system, which is below what i would recommend for a PCIe card, however he needs to specify what his system consists of, so that we can determine his power requirements, but his original question was essentially - is a Rosewill PSU quality, answer
NO.
I would much rather spend an additional £30 on this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139001 which is $110 after rebate. You get what you pay for, but i guess if you choose the PSU by its colour, then you are asking for trouble. If you have a little more to spend than this is an absolute bargain
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139006