Last week, the rather cool cats at iFixit ran a complete teardown of the 2018 Touch Bar MacBook Pro. The analysis located Intel’s new JHL7540 Thunderbolt 3 controller, introduced earlier this year as part of its “Titan Ridge” family among the notebooks components.
While the specifications for the JHL7540 lists compatibility with DisplayPort 1.4 on Intel’s product database, this also relies on graphics, which vary by MacBook Pro model.
Upon reading out to Apple for clarification, the following details were revealed:
The new 15-inch MacBook Pro with Touch Bar models support DisplayPort at High-Bit Rate 3 (HBR3), a signal standard of both DisplayPort 1.3 and DisplayPort 1.4. Apple says the dedicated Radeon Pro graphics can drive up to two 5K displays at 60Hz, each over a single stream.
The new 13-inch MacBook Pro with Touch Bar models support DisplayPort at High-Bit Rate 2 (HBR2), a signal standard of DisplayPort 1.2. This is a limitation of the Iris Plus Graphics 655 in these models, as Intel’s integrated GPUs do not support DisplayPort 1.4.
In short, the 15-inch 2018 Touch Bar MacBook Pro can theoretically supports DisplayPort 1.4, which Apple confirmed, but at least for now, the notebook still can’t drive an 8K display. It could be possible with VESA’s lossless Display Stream Compression standard, perhaps, but it’s unclear if this can be enabled down the road.
At present, the updated 13-inch and 15-inch models have the same compatibility with external displays as the previous-generation MacBook Pro: up to two 5K displays or up to four 4K displays on the 15-inch model, and up to one 5K display or up to two 4K displays on the 13-inch model.
The 2016 and 2017 Touch Bar MacBook Pro models feature Intel’s JHL6540 Thunderbolt 3 controller, which supports DisplayPort 1.2.
Apple has also confirmed that all four Thunderbolt 3 ports on the 2018 13-inch Touch Bar MacBook Pro are now full speed, compared to only the two left-facing ports on the equivalent 2016 and 2017 models.
Stay tuned for additional details as they become available.