Corsair One i300 review: "Power comes at a price"

Another year, another dazzling high-end Corsair One. That’s right, the coolest compact PC is back, with an internal hardware refresh and another price tag that makes us want to cry. The new One i300 has a few different models, with our top-end iteration retailing at a staggering $4,999 (even the cheapest version is only a thousand dollars less expensive).

Fortunately for the piratical PC producer, we’ve loved the Corsair One ever since its debut. Its intelligent internal design and brilliantly small footprint are even more impressive considering that it can put many of the best gaming PCs to shame with its performance. The i300 is no exception, but we’ll get to performance later on. For now, let’s take a look at what makes this dinky system so special.

Design & Features

At first glance, the i300 is no different to any previous Corsair One model. That’s largely because, besides the revamped component list, it isn’t! The chassis is almost identical to the very first One that Corsair released, with the same dark gunmetal casing and the same RGB strips running down either side of the front panel. The word ‘sexy’ has been over-used in reference to tech hardware for decades now, but we could live with it being used to describe this PC.

At just 20cm deep and less than 18cm wide, it’s a breathtakingly small PC for its weight class. Like its predecessors, the One i300 has perforated side panels and a single large fan at the top of the case, which draws air in and vents it through the roof. The slender design means that most of the components sit upright inside the frame, with the GPU tucked away behind the motherboard thanks to a nifty flexible PCIe riser.

As they say: 'if it ain’t broke, don’t fix it'. The Corsair One chassis needed no fixing, and while such a compact layout has its drawbacks (the top vent can get a bit warm during resource-intensive gaming), it wins more points than it loses. There have been minor changes since the original - gone is the ‘VR Ready’ HDMI output on the front I/O, replaced by a more useful USB-C port - but for the most part, this is still the same One we fell in love with a couple of years ago.

So, what is new? Well, the graphics card is arguably the most important aspect of any gaming PC, so let’s start there. The i300 is packing an Nvidia GeForce RTX 3080 Ti, one of the most powerful and best graphics cards on the market right now, with a hefty 12GB of VRAM and significantly better memory bandwidth than the original RTX 3080. It’s the ideal card to build a 4K gaming system around, which is exactly what Corsair has done. This really is an RTX 3080 PC that will go toe-to-toe with any RTX 3090 PC.

Backing up that GPU is an equally high-end CPU, the Intel Core i9-12900K. A 16-core processing powerhouse, this contender for best CPU for gaming should tear through CPU-bound games and tasks with ease. It’s joined by 64GB of shiny new super-fast DDR5 RAM; arguably more than anyone needs, but hey, this isn’t a machine for those who are shopping on a budget.

There’s no hard drive to be found here - as in, an HDD - as it would likely take up too much space inside the One’s chassis. Instead, we’ve got a 2TB high-speed SSD plugged directly into the motherboard, functioning as our primary storage. This comes with Windows 11 pre-loaded, so bear that in mind if you’re aiming to stick with Windows 10 for now (we’re sure you have your reasons).

Unfortunately for any would-be hardware modders, you’re not likely to be able to upgrade or tweak much inside the i300, just like older Corsair One models. Everything is neatly slotted away inside the case, and just opening it up for a spring clean with a can of compressed air is tricky enough. The motherboard is custom-designed to fit inside the minimalist space, and everything is tightly secured. You won’t be buying a new third-party graphics card for an upgrade in a year or two, because it just won’t fit. Thankfully, the hardware on offer here is cutting-edge enough to last for years to come.

Performance

We weren’t remotely shocked to see the Corsair One i300 obliterate our suite of game benchmarks. Even the dreaded Metro Exodus RTX benchmark, which once made 2000-series Nvidia GPUs tremble in fear, was left in the dust with a framerate well clear of 60 fps. Ray-tracing in other games sees similarly brilliant performance; Control plays like a dream on the i300 at maximum settings.

At 4K, the target resolution for this machine, basically everything runs at 60+ fps, regardless of graphical settings. Metro Exodus offers an ‘extreme’ option above 4K ultra graphics, and even that gave us more than 80 frames per second. CPU-bound games like strategy title Total War: Three Kingdoms make great use of the i9-12900K processor for similarly fantastic performance.

It’s no surprise that this machine is a beast for 4K gaming: it cleans up at any resolution if you’re rocking one of the best 4K gaming monitors or even an 8K monitor; though, going in the opposite direction, if you’re an esports nut who wants an ultra-high framerate and is willing to trade down to 1440p or 1080p to get ridiculous numbers, it'll do that too. Remember that you’ll need a high-refresh-rate panel - like one on our best gaming monitor guide - to take advantage of that, though. Speaking of esports, we took a cheeky dip into Valorant at 4K and were comfortably seeing framerates in excess of 200 fps.

Although this is first and foremost a gaming machine, it’s got more than enough hardware oomph to handle all manner of workstation-level tasks. High-end rendering and video processing work is no problem here, nor are number-crunching scientific modelling programs thanks to the powerful CPU and truckload of the best RAM for gaming. The 2TB solid state drive is also extremely fast, loading games in no time at all and shifting massive file transfers without any difficulty.

One thing we did notice was that the i9-12900K runs pretty hot under load. The Corsair One’s single-fan configuration means that its thermal performance is never going to beat a more spacious and well-ventilated case, but some of our benchmarks saw CPU temps rise as high as 97C, with noticeable heat from the top exhaust grille (though no external parts ever became too hot to touch, which was good to see).

We didn’t see any significant performance throttling, however, and the rest of the system remained relatively cool despite the scorching processor temps. Arguably the most impressive part was how quiet the i300 remained throughout our testing process, with only a slight fan hum to let us know it was under duress. The CPU is cooled by a compact all-in-one liquid cooling unit, and we couldn’t detect any noticeable whine from the pump either—a common complaint in AIO-cooled machines.

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Overall - should you buy it?

Yes, you should, if you want a new PC that offers you unbridled power. But that power comes at a price. Five thousand bucks is no small order. However, given the current state of the market building your own PC won’t be hugely cheaper and definitely won’t be as compact. Hell, the RTX 3080 Ti alone is hard to find for less than a grand and a half right now, so opting for a pre-built system makes a lot of sense. If only we all had access to those OEM wholesale prices, eh?

Really though, the Corsair One i300 is one of the best 4K gaming desktops available right now, offering blistering performance in virtually every area thanks to top-of-the-line hardware, and it does all that while packing one of the best-designed cases we’ve ever seen housing a pre-built PC. Corsair clearly knew that they were onto a winner with the One, so why mess with a good formula?

And if you fancy your gaming machines portable, be sure to check out our best gaming laptop guide right now too.