Can i have 2 different graphic cards in 1 system?

Anyway i currently have a lenovo 8gb with a geforce gt 720 which i have few complaints it is a okay setup but here in a week or 2 i'm buying around 500$ worth of upgrades to it which includes another 8gb of ram and then a GeForce GTX 770 and i have seen some places saying i can't mix them and i can so i'm curious can i have both graphic cards (GeForce GT 720 and a GTX 770 ) is that possible?

You could try, if it were worth doing. It's not with a 720, no. Even if you wanted multiple displays, the 770 can do a better job than the 720 can.

It would really depend on your motherboard, and the OS. Some configurations work, others have problems, and when it's the same card type as you would by having two Nvidia cards, well, it wouldn't.

And no, don't even worry about SLI, the 720 can't do SLI, period. Nor is it good for PhysX. It's a low-end card with a lot of stuff disabled.

If you really wanted a second card, I'd tell you to get another AMD card, but it really isn't worth the bother, most likely.

This is a laptop, right? You can't really change out graphics cards in a laptop.

No, you can't have 2 different GPU's in one system.

SLI and CrossFire are ways to have 2 graphic cards in your system. The less costy way is CrossFire with and AMD APU. If you buy a Radeon HD 6670 2gb for example and you can crossfire it with an a8- 3870k.

If your motherboard supports CrossFire AND BOTH Video cards support CrossFire, then yes it is possible.