Ifd you are talking about page rank then relating it with SERP, Page rank matters but has not major influence. In now a days the prime concern on is website is usable, is serving the purpose, how much faster it is, Is it a brand? who are recognizing it(back-link), what is its social presence. These are the major factors, if you have made your website for users, you are working to set up is a brand, it is faster, using ethical ways of Optimization you will be ranked else...
Page rank also depends on damping factor which lies between 0 to 1, usually taken as 0.89, if you are involved in any/some link buy sell activity for gaining page rank you will get penalize. The best way to create quality quantity content which people like to link back.