Very low writing speed with TB3 NVME Enclosure + SN750 MacMini M1

[phillyjoe]

Hi,

I've read other posts about this subject, but can't find an answer, yet...

I bought a new Acasis TB3 Enclosure with 1Gb NVMe (WD_Black SN750) for my MacMini M1 (OSX 11.6, 16gb/512)
With Black Magic Speed test I can read >2800 MB/sec(!), but writing speed is only round 900 MB/sec.
According to other posts it must be possible to also have a writing speed of 2800 MB/sec.

So, what's the problem?
1. My MacMini M1 port
2. My Enclosure
3. My NVMe
4. My cable (I tested two of them)
5. ...

Hope someone has the answer.

Thanks!

Philly

 

[joevt]

NVMe. Many have an issue in Thunderbolt enclosures. Gen 4 NVMe usually don't. For example, I can get 2817/2739 MB/s read/write (AmorphousDiskMark.app) from a Sabrent Rocket 4.0 2TB and 2822/2800 from a Mushkin gen4x4 4TB.
(I have a Mac mini 2018)

 

[phillyjoe]

Do I have bad luck with this item then? I see several posts on the internet about this specific NVMe (SN750) where users have a similar performance like you (on a MacMini M1)... May be Apple has a bad influence with their latest Big Sur update. I don't know. I can switch it without any problem at the store, so may be I will try a Samsung 970 EVO, 980Pro or Seagate 510 serie.

 

[joevt]

Do I have bad luck with this item then? I see several posts on the internet about this specific NVMe (SN750) where users have a similar performance like you (on a MacMini M1)... May be Apple has a bad influence with their latest Big Sur update. I don't know. I can switch it without any problem at the store, so may be I will try a Samsung 970 EVO, 980Pro or Seagate 510 serie.

Do any of those use the same Acasis enclosure?

Sometimes NVMe of the same model use different chips.

 

[Xzibit]

I'm using the Acasis right now with a Gen 4 rocket 4 plus and it doesn't work on M1 MBP. Still diagnosis the problem though.

Ive heard the M1 TB/USB has restrictions.

 

[MRxROBOT]

Hi,

I've read other posts about this subject, but can't find an answer, yet...

I bought a new Acasis TB3 Enclosure with 1Gb NVMe (WD_Black SN750) for my MacMini M1 (OSX 11.6, 16gb/512)
With Black Magic Speed test I can read >2800 MB/sec(!), but writing speed is only round 900 MB/sec.
According to other posts it must be possible to also have a writing speed of 2800 MB/sec.

So, what's the problem?
1. My MacMini M1 port
2. My Enclosure
3. My NVMe
4. My cable (I tested two of them)
5. ...

Hope someone has the answer.

Thanks!

Philly

It's #1. The M1's integration of thunderbolt neuters the write speeds. M1 Pro/Max or Intel will achieve the speeds you are after.

 

[MRxROBOT]

Did you purchase Acasis TB3 enclosure or the Acasis USB4.0/TB3 enclosure? The former seems to have much better compatibility for full throughput.