Hi TheEmuRider.
"evga SLI n41" doesn't tell us much beyond the northbridge, it's not an eVGA part #.

Anyway, it should be obvious.
It's the wrong form factor for the case or your standoffs are in the wrong holes.
The Asus board is an ATX form factor (12"x9.75")
Without an actual eVGA part#, i'm "guessing" the board may be a Micro ATX board (9.5"x9.5").
Most full size cases support multiple form factors but will require you re-install the standoffs in a different set of holes. These holes should already be pre-drilled. Case make and model would be nice too.
Do Not cut the case in the back. You'll draw in all kinds of dirt and dust in the remaining gaps for starters as well as weaken the case structure itself.
If you need to mod the case to accomadate the motherboard, (not recommended) lay the motherboard in a position were everything lines up, mark the mounting hole locations with a pencil, then drill new holes for the standoffs.
Insert the standoffs in the newly drilled holes and secure the motherboard to them.
If you find that nothing will line up, it's either a different motherboard or a different case.