either Acer V3-571G-53212G50, i5-3210M + Nvidia GT630M@RM1999, 2GB, 500GB

or

Asus
A55VD-SX520/521/522H, i5-3210M + Nvidia GT610M@RM2149[2.52kg], 2GB, 500GB, W8; colors: white/blue/red

S56CM-XX090H i5-3317U + Nvidia GT635M + 24GB mSATA + 500GB@RM2199[2.3kg], 2GB, W8; color: black

or

Dell nspiron 15R (Special Edition), i5-3210M + AMD HD7730M@RM2199, 4GB, 1TB(5400rpm); backlit keyboard optional, W7HP/W8

and Lenovo Ideapad Z580, i5-3210M + Nvidia GT640M@RM2299, 4GB, 750GB(5400rpm), W7HB, white

personally I vote for asus s56 because it got ssd and the GPU slightly weaker than others

currently no overheat issue. just have to monitor the temperature and dont let it go up to 90C when gaming.

The S56 is an ultrabook aimed for lightness and slimness

The Z580 is a mainstream notebook and has better performance but heavier weight

So its entirely up to you, if you want performance, then its the Z580 for you. Otherwise, its the S56 

15.6"
Asus [Ultrabook] S56CM-XX090H i5-3317U + Nvidia GT635M + 24GB mSATA + 500GB@RM2499[2.3kg], 2GB, W8; color: black
Lenovo
Ideapad Z580, i5-3210M + Nvidia GT640M@RM2299, 4GB, 750GB(5400rpm), W7HB, white
Ideapad Z580, i7-3612QM + Nvidia GT640M@RM2499, 4GB, 500GB(5400rpm), freeDOS, white
Ideapad Z580, i7-3612QM + Nvidia GT640M@RM2699, 4GB, 500GB(5400rpm), W7HB, white
Ideapad Y580, i7-3630QM + Nvidia GTX660M + 1920x1080 @RM2999[JBL], 4GB, 500GB(5400rpm), W7HB/W8, backlit keyboard, 2 yrs warranty
Ideapad Y580, i7-3610QM + Nvidia GTX660M (2GB) + (1920x1080) + Bluray@RM3599[JBL], 8GB, 1TB HDD(7200rpm), W7HP, backlit keyboard, 2 years international warranty
Ideapad Y580, i7-3630QM + Nvidia GTX660M (2GB) + (1920x1080) + Bluray@RM3999[JBL], 8GB, 32GB mSATA + 1TB HDD, W7HP, backlit keyboard, 2 years warranty

Actually laptop (all electronics) components are suspectible to heat
For example, HDD if constantly operated under high temp, tend to have shorter life span
Laptop, being small and has a confined space, don't dissipate heat as well as a full size desktop tower. Therefore if you get a laptop, make sure you keep it cool (using cooling pad or any other ingenious methods ... ) and keep it clean (make sure no dust block the inlet / outlet vents ... ).

Y480 has some powerful component (i7, GT650M) is a small body, tend to get warm under load (the area around HDD is particularly warm ... Best long term solution is to swap the HDD to ODD place).
Y400, from what we see, has much better thermal profile.