Unlike the CPU, with which we can achieve a stable OC, it seems the GPU is often less stable and less beneficial... On my N4, I used franko kernel, and he refused to do a GPU OC. I seem to recall a concern from franko that it would mess with stability, but I could be remembering incorrectly; maybe he just wasn't interested in the GPU. I tried an alternate kernel that had a higher GPU max frequency, and to be honest I didn't really notice a difference. Underclocking the GPU was evident, though, which is why I thought a GPU OC would help speed things up. Maybe there's a bottleneck somewhere else after 450mhz?
FWIW, I was primarily gaming with emulators, which may lean on the CPU more heavily than native android games.
On my N10, someone made a mod to make the resolution 1024x800, which helped some games. Maybe something similar could be done with the N5. On most emulators, anything beyond 480 is unnecessary anyway.
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