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Stadders

macrumors newbie
Original poster
Aug 28, 2014
11
0
West Country UK
Tempted by a Plugable Thunderbolt 3 2TB NVMe SSD . Has anyone used one as a Boot drive for a 2017iMac Retina 4K 21.5 inch 2017 3.6GHz i7 machine and how did it do?
 
Not a 2017 iMac, but my current boot drive for my Late 2012 iMac is a Samsung X5 Thunderbolt 3 NVMe drive.

I have been happy with it so far.

I have upgraded the X5 drive as it was originally 500GB. I swapped it for a 1TB Samsung 970 EVO Plus NVMe. While the read speeds between the 500GB and 1TB NVMe are basically the same, the write speed was slightly better on the original 500GB NVMe in the X5.

It very fast for my Late 2012 iMac, but since my iMac only has TB1, the X5 is performing much less than what it is capable of.

On your 2017 iMac, it would probably perform more than double than the speeds I am seeing.

It has been stable so far with no issues.
 
OP:

If you have tbolt3 ports, a tbolt3 drive is VERY fast, but it can often run "on the hot side", as well.

vertical smile -- have you had any overheating problems?
Ric Ford over at macintouch.com tried an X5 and found it got so hot that the drive controller actually "throttled back" the drive and slowed it down.

I've never had a tbolt3 drive, but I've used several 2.5" SATA SSDs as boot drives, and I also have a USB3.1 gen2 drive I put together with an nvme blade in an Orico USB3.1 gen2 enclosure.

The SATA SSDs all run cool and almost never begin to "get warm", BUT... their read speeds are limited to about 430MBps over USB3. That's not bad for general usage, but these days folks seem to want "more speed".

The USB3.1 gen2 drive is twice as fast -- 965MBps reads -- but it does "get warm" under heavy writes. Under very heavy writes, it will get on the hot side, but not so hot you can't pick it up, nor does it throttle back.

My guess is that there's -something- with nvme technology that just "produces more heat" (perhaps faster speed of electrons flowing inside). Controlling/dissipating that heat can get problematic in a small enclosure.
 
OP:

If you have tbolt3 ports, a tbolt3 drive is VERY fast, but it can often run "on the hot side", as well.

vertical smile -- have you had any overheating problems?

When I first got the drive I did some tests and noticed that the drive it self feels very hot. I was a little concerned about it, but according to the temperature sensor readings, the X5 temp under a heavy load was just a little higher than the temp of my iMac's internal SSD under no load.


Ric Ford over at macintouch.com tried an X5 and found it got so hot that the drive controller actually "throttled back" the drive and slowed it down.

I wasn't busy, so I decided to give it another test today as I started typing up this post.

At idle, the internal Apple 128GB SSD was 86° (30°C) and the X5 was 106° (41°C).

Using BMDST, with a stress of 5GB for 10 minutes, The Apple SSD increased to 133° (56°C). That is a 55% increase in temp from idle.

Using BMDST, with a stress of 5GB for 10 minutes, The X5 increased to 126° (52°C). That is a 19% increase in temp from idle.

The X5 had a 6% lower temperature under the same stress while performing about 2.5x faster than the Apple SSD. There was also no throttling that I noticed from either drive.

Caveats:
-The X5 was not running at its full potential, as I am using it as a boot drive for a Late 2012 iMac with TB1. I would assume that the X5 could have increased temps even more and potentially seeing throttling if used with TB3.

-In retrospect, I should have booted from a different drive, as my X5 as the boot drive during the test. This could have made temperatures higher than if I would have used a different boot drive. The idle temp would have probably be lower.

-Not sure if it matters, but the Apple SSD is relatively old with 86% of its life left, uptime of 44101 hours, and a power cycle count of 24232. It has 25% free space. The NVMe of the X5 is basically new at 100% life, uptime of 972 hours, and power cycle count of 317. It has 36% free space.

-I am unsure if this impacts the test at all, but I replaced the original NVMe that came with the X5 with a 1TB Samsung 970 Evo Plus. The original NVMe that came with the X5 actually performed better with write speeds.
 
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Another thing I forgot to add about the Samsung X5 is that the case looks plastic, but it is actually a big heatsink.

I think that is one reason I was so concerned about how hot it felt at first, but since it is a heatsink, I would expect it to feel hot.

It reminds me of the original Apple TV, the top of it was a huge heatsink and would get really hot.

it got so hot that the drive controller actually "throttled back" the drive and slowed it down.

I scanned a few pages of Ric Ford's review of the X5 and didn't see the part about it throttling, I could have missed it though. If you have a link to it, can you post it?

I would be curious to what speeds the X5 is being throttled to.

If the X5 is being throttled by 50% sometimes due to heat, this is still much faster than the performance that is offered by NVMe on USB3.1 Gen2 enclosures.

If it gets throttled to the point that the speed are lower than what can be achieved with USB3.1 Gen2, than I can see this as being a problem, but if they sometimes get throttled to speeds that are as high or higher than USB, I don't see this as a problem at all.
 
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Seems like Mr. Ford's experiences with the X5 started about here:
 
Seems like Mr. Ford's experiences with the X5 started about here:
Thanks for posting the link.

It is definitely interesting, and maybe I might do some more tests again. It appears that the throttling issues happen from very long writes with no breaks. Also, it isn't that the X5 has high temperatures compared to other drives, it is that the firmware has a low threshold for temp before it throttles.

According to Ric Ford, during long writes, the X5 can throttled pretty low, like USB2 speeds. Ford pointed to this from anandtech.com for a similar experience with the X5:

This is was they said about it:

We see that the thermal management scheme adopted by Samsung is very detrimental to long-running sequential write jobs (typical of first-time backups), despite managing to limit the internal SSD temperature to less than 56C. Write speeds often got down as low as 60 MBps. On the other hand, our DIY configuration with the SanDisk Extreme Pro 1TB SSD in the TEKQ Rapide aluminum Thunderbolt 3 enclosure managed to pass the same test without any issues in less than 1/10th of the time taken by the X5 for the same amount of data. The internal SSD temperature did go above the X5's (reached 57C at the end of our test), but, the passive-cooling friendly ridged aluminum enclosure managed to do an effective job.
and
Consumers would be prudent to treat the X5 as a premium product - it performs admirably for the vast majority. However, for power users who frequently transfer 100s of gigabytes in one go, a solution like our DIY Thunderbolt 3 SSD is a better choice. Our DIY device does not look as sleek as the X5, but, it is cheaper and has more consistent performance.

So, it looks like for non-stop writes of large amount of data (100GB+). An example of this would be like when first setting up a X5 as a boot drive and using CCC to clone your current boot drive.

But, the upside is that if the X5 drive is used as a typical boot drive, you would probably never see any throttling unless you start moving very large amounts of data to the drive.


Based off Ric Ford's, anandtech.com's comments, and some other comments I read, the temperature threshold for throttling is a little low for the X5, and the newer firmware may have corrected this. Ford said that he tried updating the firmware, but ran into a bunch of problems, and wasn't able to.

I will check the firmware on my X5 and see if it is newer than what Ford was using. Considering I just purchased the X5 less than two months ago, it might have newer firmware.
 
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