Hello i need plz an expert opinion on this, only one card is detected in bios gpu dim post,an in windows nvidia controle panel.normal sli works fine on my ocz fatality 750w,when i try 3 way sli i get the problem.so i was told in forums it was my psu not enough power, 850w ie recomended for 3 660 ti dc20,so i bought a new psu,antec 900 high current gamer an still same problem! I'm very frustrated.ive tried mobo bios update,card vbios update, reseat cards,try cards individually all fine,clear cmos,take out cmos button,dont know what to do again,do i need to change somthing in bios? Plz help asap plz .my spec mobo maximus v extreme,i5 3570k,3 asus 660 ti dc2o,h100i 16gb corsair vengence,1 tb wd hd,900w antec hcg psu,600t case.