Hi all, new to these forums. Please forgive the length of this post, I've got 99 problems and my rMBP's performance is all of them. I have a mid 2012 Retina MacBook Pro 15" with discrete graphics (GT 650M), 16GB ram, and the 2.6GHz CPU. Performance on all graphics intensive applications has been steadily going down hill for the last year or so. About a year ago I had to have the screen and logic board replaced as my computer was unable to start up, would crash randomly if successfully started, or had a black screen while running. These issues seemed to stem from a problem with my graphics card, and once everything was replaced this was fixed somewhat. My replacement screen still has a big blotchy imperfection as I am aware a fair number of retina screens of a certain manufacture suffer. Graphics intensive applications as I said perform terribly for a machine of these components, even on very moderate or even low settings. Some examples are XCOM: Enemy Unknown on ~1200x800 resolution and medium/low settings, Dota 2 on similar settings, Hawken on even lower settings, and Battlefield Hardline's beta on minimum settings. All games perform to a middling to poor framerate, and experience inexplicable slowdowns where FPS drops to a near crawl seemingly at random, often not in conjunction with increased intensity of graphics on screen. I have a friend with a macbook air who runs these games with no issue, a friend with a macbook retina 2013 who does the same, and even a friend with a macbook 2010-ish that can run XCOM, Dota 2, and Hawken just fine. A $3000 computer should not have problems running old games on low settings, and it was not always like this, so clearly something with the hardware must be horribly defective. I've run graphics benchmarks software that seem roughly consistent with online results, and have taken my macbook in to the apple store many times, to the point that the OS has been reinstalled more than once and my boot camp partition eliminated to try to resolve these issues. No luck. I'm at wit's end and can't explain this computer's terrible performance. I have extended applecare so taking it in on warranty is not an issue but does not seem to resolve much aside from getting them to rip the guts out and replace them as I did a year back. I have gfxCardStatus v2.3 and have confirmed that it says the discrete GPU is switching on, and have tried these programs with the graphics mode set to discrete only rather than switching. Restarting, resetting the SMC, or PRAM will sometimes temporarily fix my issues and bring my FPS back from a ridiculous 15-20 on lowest settings in Dota 2 to an acceptable 30-40 FPS on medium-high settings, with similar increases from terrible to decent for other games. This fix however never lasts, and I'm out of ideas. I've googled and googled to no end but I have not found answers. This seems to me the most knowledgeable Mac based community, could anyone who has knowledge of similar experiences shed light on my problems? Much thanks for any help offered.