All Posts by Date or last 15, 30, 90 or 180 days.
also by Lloyd: photography and

Links on this site earn me fees or commissions.
As an Amazon Associate I earn from qualifying purchases @AMAZON

Other World Computing...
B&H Photo...
Get all the tools you need to upgrade the factory HDD of any 2009-2019 iMac to a larger HDD or a modern SSD.
Upgrade the memory of your 2020 iMac up to 128GB

Why I Might Have to Abandon the 2019 iMac 5K

The 2019 iMac 5K is a terrific machine that will serve most all users extremely well. Most users will never hit the limitations I describe here. So I still highly recommend the 2019 iMac 5K for most users, including myself when traveling my Mercedes Sprinter van.

2019 iMac 5K

But alas, its one shortcoming is coming back to bite me in the ass, that is, the single Thunderbolt 3 bus with only two ports:

  • A single Thunderbolt 3 bus means that I can never run a 6K display like the Apple Pro Display XDR without hugely degrading performance of all other Thunderbolt peripherals (see Understanding Thunderbolt 3 Bandwidth). That is, a 6K display eats 30 Gbps of the 40 Gbps available on the Thunderbolt 3 bus, leaving a sluggish 10 Gbps available for data—USB speed.
  • My standard work setup already has three Thunderbolt 3 devices on the bus {OWC Thunderblade, OWC Thunderbolt 3 Dock, LaCie Bolt}, leaving only 3 peripherals possible. If I were to add a Thunderbolt 3 display or any other peripheral, only 2 others would be possible.
  • With only two ports, cabling is a mess. And it means I can never just plug in a USB-C anything without crawling under my desk and rooting around in the dark with a flashlight.
  • Thunderbolt 3 bus disconnects are increasingly bad with only two ports on one bus. It makes the whole system unreliable when connecting 5 or 6 devices—I”m afraid to breathe near any of the cables.
  • I like to to do multiple backups at once, but I can never turn on a chain of Thunderbolt devices, because none will show up if there is one too many on the bus. So I have to decable and recable to backup to all my backup drives.

The 2019 iMac 5K is such a strong machine that this limitation just stinks, a whopper of a design failure that need not have been. If this is Apple’s way of forcing people to the iMac Pro, then shame on Apple—every other pro and semi-pro Mac has dual Thunderbolt 3 busses with 4 ports!

Most likely I will have to move to whatever the next generation of iMac Pro is and sell the 2019 iMac 5K, as much as I otherwise adore it. The 2019 Mac Pro looks superb, but it is hugely expensive, and unsuitable for use for travel in my van (no display, power hungry, bulky, etc).

View all handpicked deals...

Apple 13.3" MacBook Pro M1 Chip with Retina Display (Late 2020, Space Gray)
$1899 $1399
SAVE $500 | Terms of Use | PRIVACY POLICY
Contact | About Lloyd Chambers | Consulting | Photo Tours
Mailing Lists | RSS Feeds | Twitter
Copyright © 2020 diglloyd Inc, all rights reserved.
Display info: __RETINA_INFO_STATUS__