MBP 2012 running very slow

[AdamSag]

Hi!
I have a problem with my MBP mid 2012.
A few weeks ago it suddenly extremely slowed down.
It was so slow i couldn't even perform Etrecheck.

I decided to wipe the drive and re-install os.
But the install took forever to finish. I've tried a couple of times and once even left it for 5 hours, but the install still wouldn't finish.

For a while I thought it was a drive issue, but I checked it on my PC and everything seemed to be working perfectly.

I also performed Apple hardware test and it showed no problems.

So my best guess is that the drive to motherboard cable is broken? Even though my Mac can see the drive.

Thanks for any answer!

My specs:
MBP mid 2012
128 gb Plextor M6S SSD (SATA 3)
4 GB factory RAM

PS. I've also booted ChromeOS via USB flash drive and it worked, though i couldn't install the system on my ssd.

 

[Raz0rEdge]

Depending on the age of the SSD, I would surmise that it's failing based on what you are saying. The problem is that being accessible isn't an indication of things working OK, nor is knowing that it's visible in a PC or Mac. You really need to test writing a lot of data to it and see if it can handle it.

SSDs have a finite lifetime and a clear indication of failure is slow reads and very slow writes.

 

[AdamSag]

So i did some testing of my SSD and here are the results.

CrystalDiskMark (1GB):
Seq Q32T1: Read- 520.6 MB/s Write- 332.2
4KiB Q8t8: Read- 274.3 Write- 42.54
4KiB Q32T1: Read- 182.4 Write- 50.45
4KiB Q1T1: Read- 24.94 Write- 32.60

Writing a 2,5 GB file on the ssd took about 5-7 seconds.

So to me it seems that the ssd is fine.

 

[ipadder474]

Had the same problem after an OS upgrade really ran slow, reinstalled the OS upgrade and this improved the speed.

 

[ferrarr]

It's possible the cable is bad. Do you have an external drive or enclosure you can put the drive into, then install macOS onto the external drive? This should confirm the cable is the issue, especially if you use the internal drive in the enclosure?

 

[AdamSag]

I booted ChromeOS via usb flash drive and Mac was working correctly(it booted the os, i could open up chrome and even play some YouTube without bigger problems). But i couldn’t install the os on my hard drive, as if chromeos didn’t detect my drive.

So i installed ChromeOS on my ssd using my PC and pluged it back into my Mac.

The ChromeOS would actually boot(from my ssd, not usb), but i couldn’t really do anything, because it was insanely laggy and freezeing from the begining.