Apple may be cooking up something bigger than a routine chip upgrade with the M5 MacBook Pro.
After Apple released macOS 26.3 Release Candidate to developers, references to M5 Max and M5 Ultra were discovered in the code. But interestingly, there were no reported mentions of an M5 Pro chip.
That absence has sparked speculation. Is it just beta software being incomplete? Was it an oversight? Or is Apple doing something fundamentally different this time?
A new theory suggests the answer might be far more interesting.
The missing M5 Pro reference
Historically, Apple has built separate chip designs for its Pro and Max tiers. That meant different die layouts, different scaling, and separate logic board considerations.
This time, though, things might not be so simple.
Vadim Yuryev from Max Tech pr oposes that Apple could be moving to 2.5D chip packaging for the M5 Pro and M5 Max. If true, this would allow both chips to share a single core design.
In other words:
- The M5 Pro could essentially be a cut-down M5 Max
- Fewer CPU cores
- Fewer GPU cores
- Lower RAM ceiling
- Same underlying architecture
If both chips are derived from one base design, macOS might only need references to the highest tier variant in early code builds. That could explain why M5 Max shows up but M5 Pro does not.
Suggested: M5 Max MacBook Pro Geekbench Scores Could Rival Desktop CPUs
TSMC’s role and the SoIC-mH angle
Reports have previously claimed that Apple is working with TSMC on a SoIC-mH process for the M5 Pro and Max.
That is not exactly the same as 2.5D packaging. However, some analysts believe Apple could be combining multiple advanced packaging methods to:
- Improve efficiency
- Increase performance density
- Lower manufacturing costs
- Simplify production
The 2.5D method is already used by companies like AMD and Nvidia. If Apple is adopting something similar, it could signal a shift toward more modular chip construction.
And that brings us to the M5 Ultra.
A monolithic M5 Ultra?
Yuryev also suggests that this new architecture could allow Apple to build the M5 Ultra as a monolithic die with multiple chiplets, rather than stitching together two Max chips using UltraFusion.
If that happens, it would be a major shift in Apple Silicon strategy.
UltraFusion has been effective, but a more integrated design could:
- Improve performance scaling
- Reduce latency
- Simplify manufacturing
- Potentially improve yields
That is not a small tweak. That is architectural evolution.
Why this matters for the M5 MacBook Pro
If Apple can standardize around a shared Pro and Max design:
- Fewer logic board variations
- More streamlined production
- Better supply chain efficiency
- Potentially more stable pricing
And given the current supply constraints Apple has been navigating, simplification could be a very strategic move.
It also hints that the M5 MacBook Pro might be more than just a spec bump. It could mark the beginning of a new phase for Apple Silicon design philosophy.
What happens next?
Apple is expected to refresh the M5 MacBook Pro soon in March. With macOS 26.3 nearing public release and M5 references already appearing in code, the timeline feels tight.
Whether this packaging theory proves accurate or not, one thing is clear: Apple’s chip roadmap is getting more sophisticated.
And honestly? That makes the M5 generation far more exciting than just “more cores, more speed.”
