Late 2013 iMac, 21.5 inch Running External SSD USB 3. SSD Disk Speed Queries & Upgrade to Mac OS Catalina??

Hey Old Toad,

Thanks for the input.

• Unfortunately for me, the labelling in the FIG 2A & 2B are correct, the 5400 RPM Internal HDD is running faster than the External SSD is !!!!
• I have run the Disk Speed Test on the Desktop itself, the speed is what has been shared sadly :(

Okay so I am attaching now the photos of the setup I have along with the SSD which I am running all this on.

You know what is really strange, as requested by Allan above, I ran an EtreCheck, which popped up a waring that my internal HDD is dying. Imagine that even in that state, it is managing to run faster in the Disk Speed Test, but if I try and use that to run my iMac, I may in all honesty, throw the iMac out of the window !!!! This is what baffles me, the tests say that it should be working at a great read/write speed, but actually it runs slower than the tortoise.

On the other hand, my SSD is running the entire system like it has never run before, smooth and quick, something I have never seen on this iMac since inception. BUT, the disk speed says this is the slower drive !!!! Confused !!

Do let me know what next I can do !!

Again, thank you very much Old Toad and all other friends for taking the time to chat wit me about this.

P.S: Just a small update since my first post.

• Since I have not been using this as the main computer, I thought I would try and do some testing. All my data is through iCloud, which gave me the flexibly to use this iMac for trial and error.
• Hence, I installed Catalina last night (sorry guys I am just trying this out) and surprisingly the computer does not feel slower at all. Sure there is some more time spent at the apple logo in the begging, post which I would say there has been about a 10% depreciation in initial speed. What I mean is, the first time I go to open any big application such as MS Excel, the app takes a short bit to open, but once open runs smoothly in most ways.
• As some off our friends had responded to my earlier post that the iMac will slow down a lot, so fart I am waiting decently, although I am sure once the system takes its time to settle in, things may change, either goo or bad.
• I have seen he spinning wheel a cook of times though since the update, but again only for extremely heavy requirements, the well shall show itself and quickly vanish.

Thank you

Hey All,

Thanks for the reply.

By Allan;

Let me be sure...Fig 2A is the new SSD in an external enclosure and Fig 2B is the original internal drive?

Is so, you are rightly concerned---the SDD is slower. Could the images have been mislabeled?

Response: I too thought that there has to be some kind of error here, unfortunately there is no error in the labelling of the Disk Tests, the SSD in the external enclosure is only running at that speed, even when I do a test right now !!

So the SSD I am using is the Samsung QVO 860, 1TB version. I have seen that this drive has a slightly slower speed than the 860 EVO, although the data shows a slight difference only, which I took into consideration before going for this drive as I was going to be using it externally, which would anyway cap my speed to the drive to about 350 MBps & not the current 300 Mbps. Yet this is not being achieved.

I recommend posting an EtreCheck report........

Response: I have done the EtreCheck and generated a report. I am not posting it here as of now as I am not too sure what the personal data on the report exactly and the report when generated said that some parts maybe a breach of the forum policy so I am not posting it.... Please advice how I may help proceed with that.

In a nutshell, the check has said that one HDD seems to be failing. This is the HDD which came with the iMac, 5400 RPM HDD. This is what is so troubling, the HDD which is seeming to be dying, is running at double the speed of the SSD !!!! Crazy !!!!

LEt me know what I may do next ....Cheers

Hey Old Toad,

Thanks for giving me the clarity so far.

Ive been away a few days cuz I have been doing a lot of trial and error.

So, to start with, I returned the HDD Case which I got and got a new one, the exact same Transcend as before. I did this as I wasn't sure if the cable was actually doing the trick. (on the internal 5400 RPM, I have reformatted the HDD to act as a pure storage drive for my iMac now).

Now, when I run the Disk Speed Test, the results are closer to where I would have liked (Run 1). So obviously I am ecstatic and happy to have the best I can form this old iMac.

The issue, is when I let the Disk Speed Test continue to run, the speeds for the write start dropping significantly. This will be visible in Run 4 & Run 5. I have taken these screenshots while the test was going on because the speed sometimes drops by the second time I try. ALTHOUGH, I yet do not feel the computer being sluggish or slow, even though I am now running the latest Catalina version on the SSD.

What suggestions ?? What more must I check ??

Thank you again !!

Thank you for all your guidance, Old Toad & Everyone else..

Seems that I am happy with the way things have set back to normal, Catalina is alright so far, can't really complaint...

See you guys on the next questions .. got some AirPort Extreme issues I shall post about soon ..

Thank you

I see, even running an SSD which transfers data roughly around 300-300 Mbps? (from the screenshot)

Hey BDaqua,

may you please assist me on how I may post the report here without breaching any rules or sharing anything about my iMac which could be used negatively etc.

thank you very much.

I have just done another test and am posting the same here again. Sorry for the troubles guys.