For info, official set of Y580 from Lenovo Malaysia will only be available sometime in July. Y580 currently selling in market is a imported version. The official set come  with Blue ray & 2 yrs warrantly where imported set come with DVD & 1 yr warrantly.
Y480, i7-3610QM + Nvidia GTX650M (GDDR5) @RM2499[JBL], 4GB, 500GB, DOS
N56Vz, i5-3210M + Nvidia GT650M(DDR3)@RM2699[Bang&Olufsen], 4GB, 750GB, W7HP, subwoofer
Y480 vs N56vz
2499 < 2699
i7 > i5
GT650M(GDDR5) > GT650M(DDR3)
500GB < 750GB
DOS < W7HP
14" vs 15"
Y480 is RM200 cheaper come with faster core i7 & GT650M(GDDR5) less trade in 250GB, W7HP, subwoofer, more attractive/better design but questionable warranty service imo.

Y480 is best bang of the buck for gamer in price/performance with better mobility in 14". 
N56vz is more attractive & better design  . If this is the only computer you have and u cant leave without it, try look for other as u may headache with their warranty service. 

Y480 vs N56vz interior thermal  design. Who is the winner??? 
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