Chosen Solution

Hi Guys, First time poster, long time reader and user of the guides here - big fan and love your work so first and foremost, thank you for being such an amazing resource! So my issue (and again apologies if this has already been posted and I’ve missed it): My CPU maxes out (90-100%) and the machine is virtually unusable when the charger is plugged in and the battery is actually charging (but not once fully charged). EDIT Noticed the over heating and CPU issue doesn’t occur while charging when the external displays are disconnected… does this give any clues as to what the problem might be?


I use this machine at work (I’m in networking) every day. It’s usually plugged in to charger along with two external displays using thunderbolt to HDMI cables and for a 7yr old machine it’s a work horse! Leaves the brand new windows machines in the office for dead. Being a network engineer, I definitely put it through it’s paces - running multiple virtual machines, countless excel & word docs, a ridiculous number of chrome tabs along with various other background apps (one drive, google back up & sync, etc). While I appreciate running that much would be detrimental to the performance of the machine, the fact is it handles the load perfectly fine when I’m at my desk and battery is fully charged. What bothers me is that the issue only presents itself when I take the laptop to a meeting etc, use it for a little while on battery and then start charging it back at my desk. The basics: Macbook Pro 15” Retina Late 2013Mac OS Catalina 10.15.716GB DDR3 Ram2.3GHz Quad Core i7GeForce GT 750M 2GB graphics. Previous repairs/upgrades: DC port was getting unusually hot and noticed there was some charring on the pins of the port. Replaced this Mid 2018. MacBook Pro 15" Retina Display Late 2013 MagSafe DC-In Board Replacement Battery replacement mid 2020 MacBook Pro 15" Retina Display Late 2013 Battery Replacement SSD upgrade mid 2020 https://www.samsung.com/au/memory-storaghttps://www.aliexpress.com/item/32819641… (not exactly this listing - got the adapter from a friend but this is for your reference) Machine is running a clean install after the SSD upgrade - only using 500gb (most of which are VMs). Have tried doing a SMC & PRAM reset. Regularly open up the bottom and remove dust from the main board, fans & air vents using an air gun. Screenshots are below of the stats (using iStat Menus) - to be honest while I dabble in the “handyman” side of this stuff, I’m no expert when it comes to the technical stats so apologies if I’ve missed something obvious. About:

On Battery Stats:

On Charge (very hard to take screenshots when CPU is at 98% so I’ve just taken the basics - let me know if you require additional):

This looks like a CRC failure with the read/write operations to the SSD. I’ve seen this enough times now to recognize the fingerprint of the problem. Sadly, its not something you can directing check as the issue is within the adapter and M.2 SSD interface inability to transfer the data across to the system cleanly. The best way to explain this is a mind model… Where you are trying to talk to a deaf person. You say hello! And you get back what?? You then say Hello again louder and you get a head nod. You then start your dialog but the deaf person can’t comprehend what you asked and you repeat over and over again. So a single word can make it as you got the head nod (CRC), but a string of words gets you no where! This is the CRC check not getting returned as the data arrived garbled. The CPU is getting frustrated! And the battery is likewise going nuts as the CPU is requesting more power than what the MagSafe charger is able to deliver when it also needs to charge the battery as well. OK, so we understand the issue now what? Sadly, you’ll not like my answer ;-{ You clearly are pushing your system very hard! So the first action is to reduce the CPU & Storage load as the sheer quantity of dialog going across the PCIe interface is killing you. Even that won’t fix the root issue. The issue is the adapter and M.2 SSD combo is not able to work in your system properly as its a forced fit solution. I would go with either OWC or Transcend SSD’s which are designed from the ground up to be pin compatible as well as less noisy the M.2 adapter creates. Bottomline: I don’t recommend these adapters and M.2 SSD’s! I’ve got a drawer full of them from systems I’ve taken them out of. Don’t get me wrong here! I wish Apple had embraced the M.2 interface as that would have made things so much better its when you add an adapter in a very delicate place (data wise) that the M.2 SSD solution just can’t work.