I am looking forward to buying a GPU or two but I need to know which one. You see, I'll be having Asus Maximus Vi Formula and I want a GPU with best performance in best price. These are the choices, Asus GTX 760 DC II, MSI GTX 760 Hawk, MSI GTX 760 Gaming, EVGA GTX 760, Gigabyte GTX 760 2GD, or other GPUs under $550. I could also go for SLI but not CrossfireX. Oh, one more thing, I heard that there's brand compatibility issues like, an ASUS GPU will be more performing in Asus boards rather than other brand's boards. So, please recommend me the best. I want to be set off for more than 5 years with the same PC.