Thunderbolt 1 vs USB C

Damian83

macrumors regular
Original poster
Jul 20, 2011
126
10
Hi, im planning to upgrade my apple system, imac and mb air. now i have imac 27 retina (previous model) with T1 ports and a mb air. i use a samsung ssd in a seagate TB1 enclosure as the primary hdd as i can switch any time from imac to air. now im planning to get the latest imac and a macbook 12" both with T3. i was planning to get a high-end T3 pci-e ssd like the sonnentech or the owc, but both brands are ridicolous. its impossible to find those ssd's! in fact there are more T3 ssd's (pcie of course) but ALL, and i mean ALL, are only articles on websites. so ive decided to get the samsung t3 (and this time i mean the model name, NOT thunderbolt 3!). good "scam" from samsung calling an ssd in this way. i thought t3 stays for thunderbolt3, then ive read all specs that theres nowhere a word like "thunderbolt" but its only usb 3.1 type-c, that shares same connector. now, i dont care about speed because both my actual, and the new ssd will be sata, so it doesnt matter if its 10gbps or 5bps (the samsung its 3.1 gen1). my question is if usb 3.1 is stable and reliable like t1, considering ill be use it as primary hdd. please let me decide. thanks

PS: please dont ask why im using an external ssd as primary hdd, because there are ****** solution like cloud, or others. my question isnt this. thanks!
 

ZapNZs

macrumors 68020
Jan 23, 2017
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The MacBook does not have Thunderbolt 3 - it only has USB 3.1 gen 1, so with the MacBook USB is going to be your only option. Unlike with Thunderbolt 1/2/3, USB on the Mac does not support TRIM. If you are using an external SSD as your boot drive, this is something that may or may not have effect on the SSD speed and longevity over time.

If I was going to purchase a SSD to use as a boot drive that could not support TRIM, I think I would definitely aim for something much, much bigger than what I needed, and try to find User reviews of those who have used the identical drive as an OS drive in a TRIMless environment who can confirm that the SSD's controller itself is enough to prevent dramatic write speed slowdowns over time.
 

Damian83

macrumors regular
Original poster
Jul 20, 2011
126
10
you're right the mb 12 is not TB! i cant believe! but no problem in this case. as for trim, i can use trim enabler, ive already used it in past years, before official support on osx. so both problems solved. but what about usb reliability/stability???
 

MrX8503

macrumors 68020
Sep 19, 2010
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Trim enabler will not work. You can't pass the Trim commands over USB on macOS
 

ZapNZs

macrumors 68020
Jan 23, 2017
2,310
1,155
you're right the mb 12 is not TB! i cant believe! but no problem in this case. as for trim, i can use trim enabler, ive already used it in past years, before official support on osx. so both problems solved. but what about usb reliability/stability???
As MrX noted, TRIM commands will not work over USB with Macs (although IIRC some Windows systems can) - my OS external SSDs are all Thunderbolt or eSATA so they are using TRIM, and when using a SSD without TRIM on Macs, I have had mixed experiences, and once personally experienced a significant slowdown in write speeds (it's worth noting that 80%+ of the drive was full, and this almost certainly had an effect on it). From a reliability/stability perspective, when used as an OS drive my concern would be write speeds slowing down over time if you are doing a lot of write operations (which is why I would try to get a SSD with a controller that has a good reputation for working in a TRIMless environment.)

My knowledge here is very limited, but another Member might be able to comment on which controllers clean in which situations and work best for this intended purpose.
 

Damian83

macrumors regular
Original poster
Jul 20, 2011
126
10
ok then which t3 ssd to get??? i cant find even one. and i mean bus powered. ill get a mb pro instead of the mb 12. but which ssd??

ok i found this:



but i dont understand if it will work in usb mode or t3 mode. in fact what it depends on? cable or what?? an official T3 ssd like sonnentech fusion drive its t3, but once i connect it with a standard usb-c cable it will be reconized as usb?? its so confusing...
 
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Taz Mangus

macrumors 68040
Mar 10, 2011
3,621
467
The MacBook does not have Thunderbolt 3 - it only has USB 3.1 gen 1, so with the MacBook USB is going to be your only option. Unlike with Thunderbolt 1/2/3, USB on the Mac does not support TRIM. If you are using an external SSD as your boot drive, this is something that may or may not have effect on the SSD speed and longevity over time.

If I was going to purchase a SSD to use as a boot drive that could not support TRIM, I think I would definitely aim for something much, much bigger than what I needed, and try to find User reviews of those who have used the identical drive as an OS drive in a TRIMless environment who can confirm that the SSD's controller itself is enough to prevent dramatic write speed slowdowns over time.
Actually there is a SSD manufacturer that has managed to get Trim to work over USB: https://www.angelbird.com/prod/ssd2go-pkt-1031/?category=2.
 
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MrX8503

macrumors 68020
Sep 19, 2010
2,268
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ok then which t3 ssd to get??? i cant find even one. and i mean bus powered. ill get a mb pro instead of the mb 12. but which ssd??

ok i found this:

but i dont understand if it will work in usb mode or t3 mode. in fact what it depends on? cable or what?? an official T3 ssd like sonnentech fusion drive its t3, but once i connect it with a standard usb-c cable it will be reconized as usb?? its so confusing...
Yeah it is confusing.

So the Lacie screenshot you attached "appears" to be Thunderbolt 1 and USB-C. Very misleading marketing.

How TB3 works is that it has nearly all the protocols available in a single cable/port. What this means is that if a cable/port fits, it'll work no matter what by negotiating the protocol. So if you plug a USB-C peripheral into a TB3 port, the peripheral will work, but will operate as USB.

If you plug a TB3 peripheral into a USB-C port, I don't think it'll work.
 
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