In my last post about the PlayStation 5 event, I noted that the console looks massive. Since then, a fair few comparisons have popped up. I like this one in particular, courtesy of Twitter user PadPoet
As you can see, it's absolutely gigantic - quite possibly the largest console ever made. Or at least since the OG Xbox. At the same time, the Xbox Series X is also larger than its predecessor, Xbox One X. (Though do note, it'd be roughly the same volume as the PS4 Pro showed above, overall, because it's only about a third as deep)
It's all about cooling
By now, it's widely established that the next-gen consoles will use more power than their predecessor. Some guesstimate thus far suggest it's going to utilize somewhere between 250W to 300W of power. This is a huge increase over the Xbox One X's 180W. There needs to be a way to dissipate this extra power, so the Microsoft team thought out of the box to come up with a new design. In the end, they settled on a cube reminiscent of PCs like the 2012 Mac Pro and Corsair One.
The main advantage of this design is that it allows the use of a massive fan, which is just now possible on the slim set-top-box like form factor we expect of consoles. Furthermore, it also allows an equally massive heatsink on top of the processor - once again, not possible in the older designs.
So, while Xbox Series X is certainly larger than the Xbox One X, it's not that much larger. More importantly, it's much smaller than the PS5.
Why is the PS5 so darn large, then? It's power consumption is likely to be the same as the Xbox Series X. Though it has fewer GPU cores, it runs at a much higher frequency, which is usually super-linearly less efficient. Unfortunately, unlike Microsoft, Sony didn't opt to reinvent the form factor. What we have is basically as the usual set-top-box-like console design - slim but deep.
As mentioned before, this design is simply not as efficient for cooling. So to gain the same overall cooling as the Xbox Series X, it just has to take up a much larger space. While we don't have numbers just yet, I'd say it's easily 2x the size of the Xbox Series X.
Of course, props to Sony for coming up with a whacky design. Opinion will differ, of course, some may prefer the minimalist, elegant aesthetic of the Xbox Series X, while the PS5 will appeal to those who wanted something different than the usual "black box". In terms of chassis engineering, however, Microsoft is a clear winner this generation.
PS: Images above directly from Microsoft and Sony marketing materials.