Mac system startup speed is particularly slow

Mac system startup speed is particularly slow
I don't know when my Mac system is getting slower and slower (it seems that I had slowed down after I changed the hard disk ), it takes about five minutes to start each time recently, and often crashes (about three or five days, the mouse can move, and all applications will die ). I couldn't help it last night. After searching, some netizens found that PRAM and NVRAM should be effectively reset. As a result, after I reset PRAM and NVRAM according to the method officially provided by Apple, I found that the startup speed of the computer was much faster. Now, the startup speed of my MacBook Pro is about 30 seconds, what is the concept of 5-minute vs 30-Second? If you have encountered similar problems, try this method. Www.2cto.com. On the keyboard, find the following buttons: Command, Option, P, and R. You will need to press these keys at the same time in step 4. Start the computer. Hold down the Command-Option-P-R key. You must press this key combination before the gray screen is displayed. Press and hold the above key until the computer restarts and you will hear it again. Release these keys.