Samsung SSD on El Capitan keeps crashing/ boot problems

I recently installed a Samsung EVO SSD in a 2012 MacBook Pro. So far, so good. But on two previous drive swaps, on 2010 MacBook Pros, we found that the hard drive cable failed and had to be replaced. Symptoms were pretty much exactly as you describe. The 2012 has a slightly different cable than the 2010, but it performs the same twists and turns, in particular folding over the DVD drive to go under the hard drive. One suggestion I read was to put a bit of electrical tape under the cable where it folds over the DVD drive.

I know you said that you already replaced the cable, but I wonder if somehow it still is not interfacing properly with the drive. It is odd that the old drive works OK. Some tiny difference in how the pins connect on the drive?

As you know, replacing the cable is not hard if you are already familiar with replacing the drive. I ordered a 2012 cable when I did the swap, just in case, but so far have not needed it (did put the electrical tape in place, however). I found it on Amazon for $19: Item #B00KR5QIEU

"NEW HDD Hard Drvie Cable 821-1480-a for Macbook Pro Unibody 13" A1278 2012"

Check that this is right for your Mac before ordering if you decide to try a new cable again.

Also make sure that you transferred the mounting screws from the sides of one drive to the other so that it's secure in the computer case. (Obvious, I know, but it's easy to miss.)

Good luck.

- Winston

Great photo, but actually, I was talking about electrical tape under the drive cable on top of the DVD drive, where the cable comes from the top of the DVD drive and bends down to the "floor" of the computer. The suggestion I'd read argued that the 90 degree bend where it bends over the side of the DVD drive creates a stress that allows some of the wires to break through the plastic and short on the metal edge of the DVD drive, on the underside of the cable's 90 degree bend. This is just "back" from where the cable is screwed down next to the DVD drive. So if trying to fix your existing cable by this method, I'd unscrew the two hold-down screws on the cable, and put a bit of tape on top of the DVD drive under where the cable bends over the DVD drive, then screw the cable back down.

Also make sure that the connector to the drive seems solidly connected and pushed all the way in. It may go in more easily on the old drive, and may not be fully seating on the new drive.

Good luck.

- Winston

I put the tape on the DVD case on the assumption that I wanted to do as little movement as possible of the drive cable. Much easier to bend the electrical tape around the DVD case and smooth it down tight, as sticky side was on "inside" of bend. To put it on the drive cable the tape would have to have the sticky side on the outside of its bend (outside of an "L" shape), and smoothing it onto the drive cable would stress the cable. (Not sure this is as clear as I'd like, but look at the bend in the cable and see how the tape would have to go to put it directly on the cable. Tape prefers to bend with the sticky side in, rather than out, as that's the way it curls on the tape spool.)

One other thought: try the SSD in an external case if you have one available, and see if you can start from it by holding down the Option key. Sometimes a product has a bad run, and it is possible, if not highly likely, that you got two drives in succession from the same bad run. If the drive works OK in an external case, that really points to the cable.

Good luck.

- Winston

You are welcome. Are you using the same Samsung drive and cable? Sometimes a good re-assembly solves this kind of problem.

Best,

- Winston

A few more thoughts:

1. Investigate TRIM enabler. I read something recently that said that part of what is done for enabling TRIM can be reset, which you might have done with PRAM/SMC resets, which then leaves things not working. I don't have direct experience with this, so you may need to research further.

2. Try doing a reinstall of El Capitan from the Recovery partion. This takes a while, but will not affect your files or user folder. Maybe in the transition from the old drive, or in the initial install of El Capitan if you did it that way, something got corrupted.

3. I've also read that a new OS install can greatly slow down a computer for a time while Spotlight re-indexes. My install of El Capitan was on a Mac with nothing in the user folder (essentially I set it up as a new computer) so, again, I don't really have experience with this. This might not be relevant for your situation, as I'd think the reindexing should only slow the computer, not stop it in its tracks as you've described. And this shouldn't affect startup. But I thought I'd mention it as it is a source of slowdowns.

Good luck.

- Winston

Hi Navib95:

I would definitely try enabling TRIM if it not already on. El Capitan supports it.

To enable TRIM, first save all your open documents as this will reboot your Mac.

1) launch Terminal.

2) Type "sudo trimforce enable".

3) Confirm that you want to enable trim.

4) Reboot your Mac.

To verify that TRIM is enabled, click the Apple icon in the top left of your screen. Choose "About this Mac" -> "System Report" -> "SATA/SATA Express" and look for the entry "Trim Support". It should say "yes" if trim has been enabled.

Kim

You are most welcome. Hope it stays stable.

Best,

- Winston