The Intel Iris Pro 5200 is on par with Nvidia GT 650M which is fast enough for most games as long as you use 2.5x Internal resolution (1600x1320) , no anti aliasing , 16x Aninsotropic filtering . Why would you need a dedicated GPU ?
Btw , macbook pro isn't a gaming laptop . It doesn't have good cooling to handle both dedicated GPU (built in onboard type) and CPU
A dedicated GPU like GTX 650M has 35W power consumption , pretty close to an i7's power consumption . High power consumption will draw more heat . And when you combile both of them together at full load , bam...
I have no idea about external GPU though
Btw , macbook pro isn't a gaming laptop . It doesn't have good cooling to handle both dedicated GPU (built in onboard type) and CPU
A dedicated GPU like GTX 650M has 35W power consumption , pretty close to an i7's power consumption . High power consumption will draw more heat . And when you combile both of them together at full load , bam...
I have no idea about external GPU though
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