Speeding up an older Mac

I replaced the spinning disk on my 28" iMac 5K Retina with an SSD. However, not wanting to risk dismantling the machine, the SSD is simply in a USB3 enclosure velcro’ed to the back. It’s now brilliantly fast, and it was brilliantly simple to do.

A friend of mine wants to do the same, but his Mac is rather older than mine, with only USB2, rather than USB3, to go with the Thunderbolt interface. As Thunderbolt enclosures seem to be a bit like hens’ teeth his only option if he is not to dismantle the machine seems to be to connect the SSD via USB2 - but the concern is whether a USB2 connection will be fast enough for the SSD to offer any significant speed improvement over his (SATA!) spinning disk. Has anyone here ever tried that?

Must be really old; even my old 2012 Mac mini has four USB 3.0 ports.

It will act about as fast as any USB 2.0 external drive, due to the USB 2.0 speed bottleneck, although it will have the data ready faster than a spinning drive so it might feel slightly faster than a HD.

I’m not sure it’s worth the expense to use an extenal SSD if you’re limited by its bandwidth. An SSD with USB 2.0 has a max speed of 60 MBps while USB 3.0 can reach a max speed of 640MBps.


I think he said it was 2009!

It sounds as if it won’t be worth the effort unless he can find a Thunderbolt enclosure - and I haven’t found any of those yet …

Probably about a 2011 vintage machine. There was about a year between when Apple added Thunderbolt to the Mac and when they went to USB 3.

An SSD over USB 2 would probably be faster than a spinning disk, but it’s definitely not going to take full advantage of the SSD’s speed. I’d recommend Thunderbolt instead. If you don’t want to go with an enclosure, another option would be a Thunderbolt dock that has USB 3.0 ports.

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Hmm. I have an ancient (2009) 27" iMac which got several years’ new lease on life after I replaced its slow hard platter HDD with an SSD a few years back. The process is simple enough for anyone reasonably savvy to perform – I used the iFixIt guide located below (and ensured I got all the recommended tools to perform the swap).


May be worth a try!

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I also have a 2010 iMac still going fine - I had a 2 TB HD installed in place of the DVD drive & replaced the built-in HD with a 256 GB SSD. I think with labor it was around $450 in 2015 at Crown City Computers in Pasadena, CA.

Be sure to check OWC. They have lots of Mac-specific hardware and are a very knowledgeable and reputable company to work with.


We have a 2011 iMac still going strong. Several years ago I bought a Kanex Thunderbolt 2 to USB3/ESATA adapter. Works great. I have found that the USB3 port on this is much faster than USB2, even with spinning drives.

Kanex Thunderbolt 2 to USB 3/ESATA adapter

A bit of topic I guess, but just to understand the concept here:

Is buying some portable external SSD, like the Lacie 2 TB SSD that Apple sells, cloning the 3 TB Fusion Drive I have in my Late 2015 iMac with CarbonCopyCloner (assuming I’m using less than 2 TB on the Fusion) onto the external SSD, then setting the SSD to be the bootable disk of the iMac and just leaving it connected and taped to the back…

Is this likely to get me out of the Spinning Ball situation that continuously occurs on my iMac these days? And preferably postpone the need to replace the iMac until I know whether there’s a new larger iMac Pro on the horizon… heh

Late 2015 seems too new to need this treatment- I’d make sure you’ve exhausted all other causes first…

I’ve tried the stuff I can think of. I’m going to offload some of the stuff stored on it to an external desktop storage of some sort (which I have a separate thread for here: Advice on External Desktop Storage ). Not sure if this can potentially ease up the situation. It’s currently stuck with around 129 GB free storage.

…but the disk itself makes sound as if it’s about to exit the iMac as soon as it needs to do some work. So I kind of thing there’s some issue with it.

I’m not familiar with Fusion drives, but I would expect that an SSD would still be significantly quicker, so there is a good chance that this would solve your problem.

Note that you don’t even need use Carbon Copy Cloner - Disk Utility will also clone a drive for you - you simply do a Restore To operation to the SSD (but you need to boot into recovery mode in order to be able to do this, as it clearly can’t clone the the active system drive).

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Not under most normal use, as the most commonly-used OS portions and apps are stored on the SSD part of the Fusion Drive. Over the yers I’ve always had occasional connect issues when I’ve put my iTunes library on external drives (more than 36,000 songs and a few hundred movies) so the Fusion Drive choice was a tradeoff that worked out pretty well.

CCC is free to use as long as you aren’t performing an incremental backup, it doesn’t require booting into recovery mode, and it copies over the boot partition, which SuperDuper! doesn’t (and which Disk Utility may or may not do, not sure).

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