MOTUnation.com

Thanks, Mike. I'll run those commands and then boot in safe mode. I might try one more time to reinstall the OS after that.

Also, I'll be sure to use Onyx sparingly and cautiously. I actually haven't used it for many years (probably because of your warnings). I'm just not that comfortable in Terminal yet, so those kinds of tools are appealing. I'm just as likely to screw something up in Terminal as Onyx is, but it looks like Onyx can do it on a grander scale.

For what it's worth (much!) I haven't had a system hang since taking these various steps. I won't know which thing did it (or whether it will last), but so far so good.

The new SSD will arrive in a few days, and I still plan to do a clean install from scratch and reinstall everything. I think this will be a good refresh for this machine, and I'll stick at Mojave as long as I can.

stubbsonic wrote: ↑Fri Jan 01, 2021 12:43 pm For what it's worth (much!) I haven't had a system hang since taking these various steps. I won't know which thing did it (or whether it will last), but so far so good.

The new SSD will arrive in a few days, and I still plan to do a clean install from scratch and reinstall everything. I think this will be a good refresh for this machine, and I'll stick at Mojave as long as I can.

While you are in there, you can make your 2012 Retina 802.11ac BT4 compatible with one of these:
https://www.amazon.com/Broadcom-Bcm9436 ... B00XY0GAV6

Considering that cards for the non-Retina 802.11ac BT4 2012s (like mine) cost $149. He adapts the above card but it's not a simple task.
https://subtle.design/products/80211ac/

My WiFi had crapped out completely and that card brought it back to life, better than new but $149… Ouch! I had bought and returned two used OE cards but neither worked after a month. Not much point in a laptop where the WiFi doesn't work.

Wow, great tip! Ordered!

I watched a bit of the OWC battery replacement video (enough to scare me off). But it did look like that part was pretty easily replaced.

Thanks for all your advice & help, Mike. I'm truly grateful.

SSD and wifi/BT installed. Everything works great.

Quick question: I read that the OWC SSD's use something called sandforce and that TRIM wasn't necessary. Do you think I should I turn TRIM on?

This is the model:
https://eshop.macsales.com/item/OWC/S3DAP12RT01/

That is old news, and I never subscribed to that theory. Even Sandforce drives benefitted from Trim.

BTW, unless the SSD is pretty ancient, it will not use the Sandforce controller.

Always enable Trim.

OK. Thanks.

TRIM is part of the MacOS since the 10.6.8 Supplemental Update. All Macs that boot from a blade should have TRIM enabled by default, even the SATA III SSD blade that some 2012–13s used including yours. Easy enough to see by running About this Mac and checking SATA/SATA Express tab. You should see

TRIM Support: Yes

If No, then run sudo Trimforce Enable in Terminal and answer y to the subsequent questions.

2.5" form SSDs always require that TRIM be enabled since Apple never shipped a Mac with a 2.5" SSD System drive. If connecting to a 2.5" SSD via an eSATA or Thunderbolt dock, you'll need to enable it in Terminal for those externals but it will still have no effect on your System drive. I have a twin-drive TB dock housing a pair of SSDs and I need to re-run it every time I swap drives.

TRIM cannot be enabled on any drive connected over USB (Mac only—not true for Windows and Linux).

mikehalloran wrote: ↑Sat Jan 23, 2021 2:11 pm All Macs that boot from a blade should have TRIM enabled by default

After installing the replacement, I did check and it was off ("No"). So I did run the sudo trimforce enable, and it worked as it should.

mikehalloran wrote: ↑Sat Jan 23, 2021 2:11 pm TRIM cannot be enabled on any drive connected over USB (Mac only—not true for Windows and Linux).

That's interesting. I have a 1TB SSD in a USB enclosure, and yea, the System Report doesn't show TRIM status at all. I don't do lots of writing to that disc, (it's where I parked some libraries) so I'm not too worried.