Apple’s next 14-inch and 16-inch MacBook Pro lineup is rumored to arrive around March, powered by the new M5 Pro and M5 Max chipsets. While these Apple Silicon processors are known for strong performance-per-watt, they can still run surprisingly hot under sustained, demanding workloads. The latest chatter suggests Apple may keep the existing thermal approach used in recent models, meaning the cooling system itself might not change much. Instead, the bigger improvement could come from how the M5 Pro and M5 Max are built and packaged.
A new rumor points to Apple shifting away from TSMC’s InFO (Integrated Fan-Out) packaging approach and toward a combination of SoIC-MH (Small Outline Integrated Circuit Molding-Horizontal) and a 2.5D design. The key takeaway is simple: rather than relying purely on a single, large “all-in-one” chip design that can concentrate heat in one area, Apple could move further toward a multi-block layout that spreads heat more evenly and improves manufacturing efficiency.
It’s important to separate the terms being discussed. SoIC-MH and 2.5D are related ideas, but they aren’t the exact same thing. In this rumor, SoIC-MH is referenced as part of the overall design approach, while 2.5D is the packaging technology that helps connect multiple chip components more efficiently. InFO packaging is often favored for very thin devices where compactness and efficiency are the top priorities. But as Apple Silicon continues to grow in complexity and size—especially at the “Pro” and “Max” tier—the limits of InFO become more noticeable. That’s where a 2.5D approach can make more sense.
One of the biggest benefits here is heat management. When CPU and GPU components are packed into a single monolithic die, heat can build up into a concentrated hotspot. If a laptop uses a relatively conservative cooling solution, clearing that heat quickly becomes difficult, especially during long rendering jobs, heavy video exports, or sustained gaming workloads. A multi-block approach can distribute thermal load across a broader area, helping reduce hotspots and making it easier for the cooling system to keep temperatures under control.
There’s also a manufacturing and cost advantage. If the CPU and GPU blocks are produced as separate components, Apple can test them individually. If one block has defects, it can be swapped out without discarding the entire chip. That can improve yields and lower production costs—an especially meaningful factor when memory pricing and supply constraints, including ongoing DRAM pressures, affect overall bill-of-materials.
Real-world thermals are part of why this rumor is getting attention. A reported example from a MacBook Pro equipped with an M4 Max configuration noted extreme peak power draw under heavy load and temperatures climbing as high as 110°C. Even chips that generally consume less power can still run hot when pushed, with stress tests seeing temperatures near 99°C. These kinds of numbers highlight why packaging and layout changes—beyond just raw efficiency—matter for next-generation MacBook Pro performance.
If Apple does adopt SoIC-MH and 2.5D packaging for the M5 Pro and M5 Max, it could set the direction for future Apple Silicon releases as well. With expectations building around Apple’s eventual move to 2nm-class chips for Macs, many observers believe these packaging and design strategies could carry forward into the M6 generation and beyond.
For now, nothing is officially confirmed, but the rumor paints a clear picture of Apple improving MacBook Pro thermals and production efficiency not by redesigning the laptop’s cooling hardware, but by upgrading what’s inside the chip itself—how it’s built, how heat spreads across it, and how efficiently it can be manufactured at scale.
