'''This would be an advanced DIY project''' (it's not easy to get the display apart without damage), and reassembly can be problematic locating the adhesive. The matte/glossy difference is the LCD. Your vendor should be able to ensure/answer resolution functionality. ''You might want to opt for changing the entire top case as a single unit.''
'''Yes there are [http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-unibody-faq/macbook-pro-unibody-video-processor-types-nvidia-dedicated-integrated.html|different graphics cards] and you must know which is in your unit.''' Two of the i7 Mid '12 models are capable of automatically switching between graphics processors, the i5 and one of the i7s are not.
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