RAD1FX :
KuLee :
No you need exactly the same gpu to use as sli for example gtx 690 + gtx690 you can only use 2 of the same card as SLI
thank you for quick response, but I've seen some videos that two different GPUs are installed in one machine
Im sorry to bring you bad news but i repeat you cannot add 2 different gpus in SLI
the videos you seen are 2 video cards in one pc not SLI tho
You can use 2 gpus in one pc if you want to use it for example with another monitor but with SLI no
i'm sorry