ye mate you should look at healthy and performance chart..you cant fix any problem with dat but its a good app to show us whats going on ..Ok, so it shows 69 for the CPU and 66 for the GPU, slightly higher than you suggested, but I still doubt that it's an issue.
@Sir Are you suggesting to take the internal HDD out and test it with HD Sentinel?
Hm, I still have a 2TB 2.5" lying around here, perhaps I should put that in, if I wasn't so lazy, then I also could put most of my games just to internal and wouldn't need the external anymore.
first take a backup if there is important data on your 2tb nd go to change the hdd after making sure that your org hdd is gone.