Ho, Bit-Techies! So, the time has finally come to start upgrading my hardware (and hopefully beggining the process of doing some case modding for the first time in 6 years!). I've decided to go with the following: Asus Maximus VI Formula i5-4690K 3.5Ghz G.Skill Ripjaws X DDR3 1600 PC3-12800 8GB 2x4GB CL7 Asus GTX 770 DirectCU II OC 2GB GDDR5 Ok, so far I've already got the motherboard and gpu, the cpu will be OC'd as soon as I can gather the components to set up a watercooling loop, and the memories will be expanded with two extra modules, reaching 16GB. Problem is I've never assembled a SLI system, only crossfire. My question is: if I were to upgrade the system with a second GTX770, does it have to be the exact same model? I know it has to be of the 770 family, but could I, for example, upgrade with a GTX770 with 4GB DDR5 instead of the 2GB? Thank you beforehand for taking the time to read!