Quick question looking for a quick answer #iATKOS #ML2

I was giving these for a perfect build

motherboard asus p8z77 m-pro

16 gig of ram corsair 1600 mhz

grafic cards geforce gtx 660 ti

cpu i7 3770k ivy bridge

power supply corsair 600w

ssd 120g sandisk extreme + hdd Seagate Barracuda 500gb SATA 6Gb/

case cooler master you have a lot of choice



I bought everything and hooked everything up the only thing is one of my sticks of ram were defective so now instead of 16 gigs I have 12 gigs I ordered a new stick should arrive soon can I still go along and install mountain lion and win7 with only 12 gigs or should I wait till i get the stick





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