Originally released in November 2001, Microsoft’s Xbox gaming console was the company’s answer to fierce competition from the Sony Playstation 2. Five years later, 24 million original Xbox consoles were sold, and cult classics like the Halo franchise were born. Since the original Xbox, the gaming console market has continued to march forward with each generation getting more and more powerful, and the latest generation is no exception. Coming in two variants, a lower cost 1080p capable machine called the Xbox Series S, and a premium 4k capable console called the Xbox Series X. Today, we’re going to open up the premium model on this edition of Change Notice.
Opening up the Series X was extremely straightforward for a consumer electronic device, requiring the removal of just two green T8 screws and a handful of clips. Inside, we see three main components: the optical drive, the fan assembly, and the motherboard/heat sink assembly. From looking at the inside of the device, it’s clear that the team at Microsoft had two goals: move as much heat as possible out of the product to support the next generation computing power, and keep the acoustics down to acceptable levels.
Opening the Xbox Series X.
Fan Assembly and Optical Drive
Removing the fan assembly first, it consists of an off the shelf 130mm diameter fan, about the same size as your average computer fan, but is surrounded by a custom plastic fairing complete with an in-mold Master Chief logo. The fairing also features some die-cut, gap fill foam, likely the first of many small parts to help keep the device quiet. Given the size of this fan relative to the air volume inside the device, it’s another indication that the team had some serious thermal demands to take care of. After the fan assembly, the optical drive comes out without much fuss. Strange to see an optical drive in a modern device, but the Series X is designed to be backwards compatible with original Xbox games, so you can still fire up your 22 year old copy of Halo.
Removing the fan assembly on the Xbox Series X.
Main Motherboard Assembly
With the fan and optical drive out of the way, we have access to slide out the main motherboard assembly. Most notably on this assembly is a large rubber strap seemingly holding everything together. While not responsible for retaining any components, this strap likely helps isolate this assembly from the surrounding case to achieve the acoustic goals.
Unstrapping the assembly we find a power supply unit with a fascinating cable retention feature for the incoming AC power. Instead of cable clips taped on to the shield cans, or a piece of tape holding the cable down, Microsoft has a custom plastic component heat staked into the shield can. We’re not sure what the backstory is behind this massive clip, but our guess is that this is another component designed to help keep vibration down, or a part designed to mitigate emissions from the noisy AC power.
After removing the power supply unit, we’re left with a substantial sandwich of printed circuit boards, a heat sink, an aluminum casting, and deep-drawn shield cans. This entire sandwich is oriented parallel to the airflow from the fan on top, so it looks like the stacking of the PCBs is a way to create air channels aligned with the direction of airflow to expose as much of the PCB as possible. Taking apart this sandwich uncovered different thermal interface materials, more nods to the thermal demands of the product, as well as an interesting no-stuffed shield fence. Looking at other teardowns on the internet, it appears early versions of the hardware had a shield fence, but more current versions like the one we took apart omitted the fence. The idea of adjusting hardware in the field after mass production has begun is not unusual, and is usually a way to remove cost from the product when the company has enough time to study the impact of removing the part. It’s impossible to tell exactly what Microsoft learned about this shield fence, but the device is certainly more cost effective in some way without it.
The main motherboard assembly on the Xbox Series X.
Heat Sink Details
On top of the main computing PCB we have a monster heat sink attached to an X-shaped sprung piece of sheet metal. This X shaped backing is a common way to apply significant pre-load to a heat sink to ensure proper bond line thickness for the thermal interface material. Sure enough, when removing the heat sink we see that the X shaped piece is concentrating the pressure around the eight-core CPU. In fact, the CPU also has a different color of thermal interface material, giving more indication that this was a critical tolerance to control.
Looking at the heat sink in more detail, on the chip side we see a clever vapor chamber plate at the base of the heat sink. This is likely to minimize resistance of the horizontal spreading of the thermal energy from the relatively small chip surface area to the much larger heat sink. On top of the heat sink, aluminum fins are attached as a separate part to spread the thermal energy into the airstream from the main fan. Whatever resistive wins the team got from using the vapor chamber must far outweigh the decision to create a bit more resistance by attaching fins instead of skiving or similar one-piece strategies.
The heat sink on the Xbox Series X.
With everything removed from the plastic enclosure, we can take a look at the design of the outer shell, and it is one of the most impressive plastic parts we’ve seen. It seems to have no draft angles, but features complex geometry on nearly every side. Our guess is that this part comes from an extremely complicated tool with actions on all sides as well as a collapsible core. It’s about as tough as you can get for an injection molded part, with the exception of some extremely long aspect ratios. To combine a complex plastic part like this with the main cosmetic part of the product is a decision that certainly led to quite a few long nights, or at least a significant number of hands on deck to make this part a reality.
Overall, the Series X is a great bit of Product Design given the intense thermal and acoustic demands. We were impressed at how much the team fit inside of the enclosure, as well as the complexity of some of the individual piece parts like the vapor chamber and the outer enclosure. Given all that we’ve seen, it makes sense that Microsoft is calling it the fastest selling Xbox to date, and that’s despite the fact that these consoles can be hard to find in stock.
The vapor chamber on the Xbox Series X.
That’s all for today! Thanks for reading.
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