• Sony’s PS5 is one of the biggest video game consoles ever, and now we finally know why.
• According to one of the principal engineers behind the PlayStation 5, the cooling fan determined the size of the console, with one large fan better than two smaller fans.
• Sony could have made a smaller console with two fans, but the PS5 could have been more expensive as a result, and so would have cost more in retail as well.

Sony finally showed us the design of the PS5 during a Future of Gaming event, but we walked away from many of the questions we were facing. We still don’t know the price, release date, games that will be available on Day One, or what the UI will look like. Many of these puzzles have been solved, but this week, we finally got the answer to the most important question of all: Why is the PS5 so huge?

In an interview with Nikkei Xtech On Tuesday, Yasuhiro Autori, Sony Interactive Entertainment VP’s vice president of mechanical design (which you may remember from this PS5 video), explained that the cooling fan is the reason behind the PS5’s so bulky. This key component was essential to cool down the motherboard.

According to Autori, the cooling fan inside the PS5 is 45mm thick. That’s thicker than the PS4 and PS4 Pro’s cooling fan. The size of the cooling fan determines the size of the console, as it is the largest component within the PS5 chassis by width. We also took a look at the mainboard that powers the PS5 in the teardown video, and the reason Sony chose to install a huge double-sided cooling fan is because air is sucked in from both sides to cool the “side A” and the “side B” of the board. The B side of the system doesn’t have a chip installed on it, but Ootori says it still generates the same amount of heat as the PS4’s SoC.

Autori revealed: “The PlayStation 5 could have been further developed to be smaller” (Translated by Chronicle Video Games). “For example, by using two cooling fans, one for side A and side B, it was possible to reduce the size of the PlayStation 5. However, there is of course the additional cost associated with having fans. In addition, controlling the functions of two fans is more difficult than just One fan With these additional hurdles in mind, we decided to cool the sides of the mainboard with one large fan. ”

In other words, the PS5 didn’t have to be as big as it was in the end, but the unprecedented size was something Sony was willing to concede to build a console that could be relatively affordable and would run quietly and efficiently. If Sony chose to use two fans instead of one, the company likely wouldn’t be able to reach $ 399 for the PS5 digital edition, which uses the same fan and mainboard as the standard PS5.