2018 MacBook Pro’s Thunderbolt 3 suffers big limitations

2018 MacBook Pro’s Thunderbolt 3 suffers big limitations


The 2018 MacBook Pro is expected to look much like its predecessor.
Despite faster connections, display support hasn’t improved.
Photo: Apple

Apple’s new MacBook Pro lineup has a lot of improvements under the hood that you might have missed. One of those is an upgraded Thunderbolt 3 controller from Intel.

Both the 13- and 15-inch models pack a new “Titan Ridge” chip, but unfortunately for some users, there are big limitations. Don’t rush out to blow your savings on an 8K monitor just yet.

When iFixit tore apart the new MacBook Pro earlier this week, its biggest discovery was a silicone membrane inside its keyboard that prevents small particles from entering its butterfly switches and rendering them useless.

But iFixit also spotted an Intel JHL7540 Thunderbolt controller, which was introduced earlier this year as part of its Titan Ridge family. But it’s not as exciting as it sounds.

Titan Ridge reaches the MacBook Pro

Titan Ridge brings DisplayPort 1.4 support, which can achieve a bandwidth of 32.4 Gbps. This allows it to power 4K displays at a faster 120Hz, and even sharper 8K displays at the standard 60Hz. But that’s not the case with the new MacBook Pro.

It seems that, despite a Titan Ridge controller, the graphics chips inside Apple’s latest notebooks aren’t quite beefy enough to power 8K displays. In fact, there are no real upgrades in display support at all.

The best you’ll get is support for two 5K displays at 60Hz, but that’s only with the 15-inch MacBook Pro with Radeon Pro graphics, Apple confirmed to MacRumors.

The 13-inch MacBook Pro, which can be configured with Iris Plus Graphics 655 if you’re willing to pay more, supports just one 5K display or two 4K displays. This is because this Iris Graphics chip does not support DisplayPort 1.4.

Display support hasn’t changed

As things stand, then, the 2018 MacBook Pro lineup offers the same support for external displays as the 2016 and 2017 models, which use a JHL6540 Thunderbolt controller with support for DisplayPort 1.2.

There is one big improvement you can enjoy now, however. Apple has confirmed that all four Thunderbolt 3 ports on the 13-inch MacBook Pro now run at full speed. With previous models, only the two ports on the left side of the machine offered this.


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