You get higher ranks by your amount of posts and you get Platinum border at 320 posts
Will link all ranks if i find it

EDIT -
Fresh Boarder (0-19 Posts)
Junior Boarder (20-39)
Senior Boarder (40-79)
Expert Boarder (80-159)
Gold Boarder (160-319)
Platinum Boarder (320+)

You get higher ranks by your amount of posts and you get Platinum border at 320 posts Will link all ranks if i find it EDIT - Fresh Boarder (0-19 Posts) Junior Boarder (20-39) Senior Boarder (40-79) Expert Boarder (80-159) Gold Boarder (160-319) Platinum Boarder (320+)