get a bigger case, get a smaller gpu or mod your case to fit the card
The cheapest solution is to mod the case. Your going to have to cut it with a dremel. You really should check stuff like this before buying such expensive hardware. I know i would. Just cut or bend everything until it fits. Its going to damage the case but oh well.
Get a bigger case. I'm afraid your current case would have bad airflow if u mod it.