Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Imac SSD boot disc problem

W

Wrighty67

macrumors newbie
Original poster
Jun 13, 2020
12
0
Hi all

I have a late 2013 Imac running Cataline 10.15.7 Intel I5 which had been running very slowly for a while. I purchased an external usb 3 ssd to use as boot disc and got myself up and running with a clean install.

The issue is that despite the USB hub showing the disc plugged in, with speeds available up to 5gb/s (the disc itself is capable of up to 6) the actual read write speed is not exceeding 80mbps and so the machine is still extremely sluggish with the beach ball showing very regularly on doing almost anything.

I have tried almost all the suggested fixes (PRAM etc resets) but have come to a dead end as to what else to try to release more speed - I have also tried different port but no change.

The SSD has is 256gb and has 200gb free space on it.

I would welcome any suggestions as to what I might be able to try to make things faster.

Many thanks

Wrighty.
 
What make of SSD did you purchase? Is it a case that you fitted a SSD into? It almost looks like its seeing it as a USB2 device. Has it a captive cable, if not make sure you are using a USB3 cable.
My solution with my old 2011 iMac (USB2 only) was to purchase an old Lacie Thunderbolt drive (ebay), the one with the captive Thunderbolt 1 / 2 cable. Remove the drive and replace with a SSD drive. That gave me over 400Mb/s. However as your system has USB3 my solution should not be required.
 
dcmaccam said:
What make of SSD did you purchase? Is it a case that you fitted a SSD into? It almost looks like its seeing it as a USB2 device. Has it a captive cable, if not make sure you are using a USB3 cable.
My solution with my old 2011 iMac (USB2 only) was to purchase an old Lacie Thunderbolt drive (ebay), the one with the captive Thunderbolt 1 / 2 cable. Remove the drive and replace with a SSD drive. That gave me over 400Mb/s. However as your system has USB3 my solution should not be required.
Click to expand...
It does seem that way, although the hub shows as speeds up to 5gb's. The SSD is made by Patriot burst and is a cheap one, but it does say speeds up to 6gb/s. The cable is the one supplied with it, stated as a USB 3.0 so should be ok.

Thats a good solution with the Lacie - thanks.
 
Did you use Black Magic speed test? Could you not try the drive in another machine to verify the speed. With regards the Lacie setup I use. I put a Samsung 860 EVO inside the Thunderbolt drive and cable-tied it to the stand I also obtained another Thunderbolt drive and put in a 2Tb spinning drive for use with time machine.
 
dcmaccam said:
Did you use Black Magic speed test? Could you not try the drive in another machine to verify the speed. With regards the Lacie setup I use. I put a Samsung 860 EVO inside the Thunderbolt drive and cable-tied it to the stand I also obtained another Thunderbolt drive and put in a 2Tb spinning drive for use with time machine.
Click to expand...
Yes, I guess I could plug it into the MacBook Air we own and test it that way.

Thanks.
 
First this may sound like a dumb question, but ... have you gone to the startup disk preference pane and set the SSD to be the new boot drive?

An external USB3 SSD, in a proper enclosure, using a USB3 cable, should give write speeds around 420-430MBps with reads in the 350MBps range (roughly). I speak from years of experience booting and running from external USB3 SSDs.

It could be:
- the drive itself
- the enclosure you're using (if the enclosure isn't "integrated into" the drive, as in "pre-built, ready-to-use")
- the connecting cable

Actually, I'd try a DIFFERENT cable as the first step.
Make sure it's a USB3 cable with the "blue-colored" ends.

Try different USB3 ports on the back of the iMac.
That means EVERY ONE of them. Test each port for speed.

If you have ANOTHER Mac to test it with, by all means do that too.
 
Fishrrman said:
First this may sound like a dumb question, but ... have you gone to the startup disk preference pane and set the SSD to be the new boot drive?

An external USB3 SSD, in a proper enclosure, using a USB3 cable, should give write speeds around 420-430MBps with reads in the 350MBps range (roughly). I speak from years of experience booting and running from external USB3 SSDs.

It could be:
- the drive itself
- the enclosure you're using (if the enclosure isn't "integrated into" the drive, as in "pre-built, ready-to-use")
- the connecting cable

Actually, I'd try a DIFFERENT cable as the first step.
Make sure it's a USB3 cable with the "blue-colored" ends.

Try different USB3 ports on the back of the iMac.
That means EVERY ONE of them. Test each port for speed.

If you have ANOTHER Mac to test it with, by all means do that too.
Click to expand...
Hi, yes its set as start up disc and it is in its own enclosure that it came in. I don’t have another USB 3 cable but can order one.
 
dcmaccam said:
Before ordering a new cable try it in your macbook air. Plug it in and do a Black Magic speed test. Post the results. 👍🏻
Click to expand...
I have tested it on the Air - 70-80mbs speed so no better. I have ordered a new cable and will try that otherwise I guess it must be the drive?
 
dcmaccam said:
Before ordering a new cable try it in your macbook air. Plug it in and do a Black Magic speed test. Post the results. 👍🏻
Click to expand...
New cable installed but sadly no improvement at 80mbps. Interestingly I did see speed of 200mbps for a short while yesterday so not sure what’s going on.
 
Looks like the drive. I would stick to a known brand. I bought bought a couple of these from Amazon uk

www.amazon.co.uk

ORICO 2.5-Inch Toolfree Hard Drive Enclosure, SATA 3 to USB 3.0 External HDD SSD Caddy Reader Adapter with UASP, Compatible with MacBook Windows Linux PS4 Xbox and More.

Turn a 2.5" SATA Hard Drive Into A UASP-Supported USB 3.0 External Hard Drive This USB 3.0 Hard Drive Enclosure with UASP lets you connect a 2.5" SATA III hard drive (HDD) through an available USB port. The enclosure delivers optimal performance with a USB 3.0 connection, but is backwards compati...
www.amazon.co.uk

and tried one with an old Samsung 840 evo. Got speeds of 338Mbs write and 388Mbs read.
 
As an Amazon Associate we earn from qualifying purchases.
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back