No need for sli or 4 slots for the ram motherboard. Z77 will overclock the cpu if it's a "k" series; B75 won't. None K cpus won't overclock except for the mild turbo setting on any motherboard. The gigabyte board with free ram will run ok; just has older ports. If you need an hdmi port for blue-ray and go with the gigabyte b75, be sure your video card has it.