Welcome to the forums.
I wouldn't risk an x1950pro on a cheap PSU like that, you would be much better off getting a decent branded one, also these guys will replace the x1950pro if it found to be faulty, but i would personally stay away from the HIS and get another brand as the HIS x1950pro's are absolutely terrible, theres loads of them faulty, id remove that link to the PSU as well as that will be classed as a competitor which is not allowed, and you would really benefit from more memory to, 512mb is very low these days, 2gb is the norm now.