not really..a newly manufactured P5N E SLi is not available anymore..the ones available are OLD STOCKs with a hell lot of problems..its very difficult to find a P5N E SLi that does not have any memory or Sata controller issues..avoid it.. 650i for SLi wont help in getting nice performance from SLi.the chipset itself is buggy..
you need 680 , 750..which are costly..
if you can get a used p5n32sli it would be great..but not if u plan to own a quad.
ps: i m selling a 680i for 7k (the above statement has nothing to do with it)