Any EVGA card can be used to enter the Step Up program provided that you purchased the card new from an authorized EVGA seller. Refurbished and B stock items are not eligible nor are items sold on Amazon that aren't directly "sold and shipped by Amazon" so be careful and pay attention to where you're buying it. 
 
Here's the list of authorized EVGA resellers:
https://www.evga.com/products/wheretobuy.aspx
 
As for what you can step up to, it's only what is available in the Step Up list here:
https://www.evga.com/support/stepup/