オリジナル投稿者： lemerise ,
I agree with Dan that you should replace the old HD cable with a new one. This MBP 13” 2012 has two problems, the HD cable and the lower ram slot. I would try to remove the ram stick in the lower slot and try the machine to see if there’s a gain in performance. When swapping a new hard drive it’s time to also replace the cooling paste under the heatsink, clean the fan and the fan output fins of the heatsink. If the Macbook runs too hot you’ll lose performance. Did you do this cleaning ?