What is the best video card? I want to connect 4 monitors. also i have a 800w psu and a i7
That's a more complicated question that you're providing information for. It depends on what you want to do with the video card. Do you play games? How much do you want to spend ($50 or $500)? What monitors do you have currently, or are you buying new ones (we need to know what inputs your monitors can use)? What CPU & motherboard do you have (use CPU-Z)? If it's Z68 motherboard with video out, then you can already use two video outs on the motherboard and get any video card. What country are you in? How and where do you plan to buy the video card?
Will you be playing games? If so, that's a solid choice that you just linked. It's a bit pricey, but takes care of everything for you in one convenient package. Besides, it may be cheaper once you factor in the price of display port adapters.
If you'll only be doing spreadsheets or watching TV, then you could go with dual cheap cards and it'll do the exact same thing. Does your motherboard have multiple full length PCI-e slots?