imac 2019 27in 5k. upgrade question

-g wrote:

I recall USB-C is limited to 900MBs on 2019 Mac hardware

As far as I know, no Mac has

• USB-C ports that support USB 3.2 Gen 2x2 – the fastest USB 3.* speed USB-C can handle
• USB-A ports that support USB 3.1 Gen 2 – the fastest USB 3.* speed USB-A can handle

There are a lot of Macs with

• USB-C ports that support USB 3.1 Gen 2
• USB-A ports that support USB 3.0. (If you go back far enough, before 2012, you can find Macs with USB 2 or even USB 1.)

Apple Silicon Macs with M-series chips support USB4. In USB4, there are three incompatible "up to 20 Gbps" USB transfer modes. If I'm not mistaken, the standard mandates support for one of the new modes ("USB4 20 Gbps"), but not for USB 3.2 Gen 2x2. In essence, the USB Implementer's Forum said it was fine for vendors to throw USB 3.2 Gen 2x2 "under the bus", and Apple did just that.

Servant of Cats

MartinR

honestly I get lost in all the USB specs and manufacturers claims and disclaimers

I am interested in learning new stuff

I even went to macsales and looked up their OWC Express 1M2 80G

OWC site states their enclosure is USB4 and we're talking about 2019 hardware (Thunderbolt 3)

Silicon m-series Macs obviously changed the rules -- my ACASIS enclosure sustains 2500MBs on 2019 Intel and M3 silicon -- macsales notes "Thunderbolt 3 host (Mac only) up to 2800 MBs"

tho I would bet that OWC USB4 enclosure -- with its purported 6000MBs M.2-NVMe speed -- only delivers under 1000MBs on 2019 iMac through its thunderbolt 3 port

that's why I asked if anyone has tested an OWC Express 1M2 80G on 2019 hardware -- it look pretty cool in theory

Dear all I have a similar question

I have a imac 2019 i9 27 inch which I use occasionally and I abolutely love the gorveous 5K monitor. I use more often however my newer silicon macook 14 pro. I have upgraded the imac with 64gb ram and I also have an external thurnerbolt case with a samsung 990 pro 4tb inside. The imac gets too hot up to 90 C degrees within some minutes I work with some intensity. It might need some new thermal paste I heard or get red of the dust. My question would be, does it worth once I have it opened to replace the internal default nvme drive of apple (512 gb) with the external samsung (I think I need an adapter). Would it be faster and more convenient to install there the macOS? even with open legacy to get newer version? I am a medical doctor so I use it mostlz for work, emails, browsing and some basic photoshop. Please tell me if the endauver does worth or not for an old machine..for older patients at least, we rather avoid operations... Thanks in advance, Best regards Michael

Dear friends

Thanks for your valuable replies. No open legacy, is hacking and I want clear and stable solutions. No resources for adventures

My remaining questions:

Since I have this combination mentioned previously Thunderbolt external M.2 SSD: about 2600MBs read/write

i recommend ACASIS TBU405 Pro enclosure and Samsung 990 Pro SSD

is it wise and safe also from temperature perspective to format my iMac and use the external nvme for first drive for main usage of MacOs? Is it safe? Fast will be, I totally understand

Second and last question, do I have to open the iMac and do anything about the temperatures? Or should I even avoid that? I think It goes up to 70 C degrees and when multitasking it reaches more than 90. Is something I can do myself of should I send it for service? In Switzerland it may cost 200USD such a checkup so I wanted if it worths the investment. I mainly use my MacBook Pro 14 m1 pro

Thank you guys, all the best

Michael

I have not. It's the published specs.

Granted more expensive TB drives should deliver better performance. Wether its required or not I cannot say.

you are probably gonna have to use a separate monitor for that