Thin designs usually don't go well with performance, as performance is compromised in order to achieve the thinness.
Certainly not recommended for heavy gaming either.

However, the Acer M5 is something you can look at. Priced at 2.9, 3rd gen i5 proc with gt640m for discrete graphics, which is pretty impressive for thin and light.
On the other hand, we have the Dell Inspiron 14z as well, packing i7 proc, with amd graphics, priced at 2.9 as well.

If you can settle for something less ultrabook like, then you should consider the y580 as well, pricing is similar to the previous mentioned models, while having a i7 and gt650 graphics.
Not forget to mention that is has Full-HD display as well.

I think you're going to have to compromise on slimness if you want performance vice versa
14"
Performance:
Dell Inspiron 14R (Special Edition), i7-3612QM + Nvidia GT640M(28nm Kepler)@RM2799[2.38kg], 8GB, 1TB(5400rpm); backlit keyboard optional
Lenovo
Y480(5934-7549), i7-3630QM + Nvidia GT650M (GDDR5) @RM2599 [JBL], 4GB, 500GB(5400rpm), backlit keyboard, freeDOS, 2 yrs warranty, P950 headset
Y480(5934-1372), i7-3610QM + Nvidia GT650(GDDR5)@RM2699[JBL], 4GB, 500GB(5400rpm), backlit keyboard, W7HB, 2 years international warranty
Toshiba Satellite M840-1009XG/XP/XQ, i7-3612QM + AMD HD7670M@RM2999[2kg], 4GB, 750GB, W7HP; colors: Gold/Pink/Blue

Portability (Slimness)
Dell [Ultrabook]Inspiron 14z, i7-3517U + AMD HD7570M + 32GB SSD + 500GB(5400rpm)@RM2899[1.87kg], 8GB, 500GB(5400rpm) *no VGA port, OD