Spec Analysis: Steam Deck - can it really handle triple-A PC gaming?

There had been rumours, rumblings and actual, solid reporting of a handheld from Valve for some time now, but the hardware has finally broken cover - and it's looking promising. Steam Deck is built on the same architectural building blocks as the new consoles from Sony and Microsoft, downscaled and refactored for a handheld. With up to 1.6TF of GPU compute power aimed at delivering circa 720p gaming, the idea is to break PC gaming free from the traditional limitations of the PC itself. It's a handheld designed to be as liberating as Nintendo Switch, but tied into the openness and sheer size of the Steam ecosystem.

There have been outsize PC handhelds before, of course, and it should be stressed that the Steam Deck is a bit of a beast. It measures 29.8cm across, almost 6cm longer than a standard Nintendo Switch, which already felt somewhat on the larger side for a mobile console. Its size is almost certainly dictated by two factors - the amount of power flowing through the machine and the need to dissipate the heat generated. More area effectively gives the hardware engineers more possibilities in keeping the device cool. The second crucial factor concerns battery life: the processor alone tops out at drawing 15W of power, so a meaty 40WHr battery is included and that requires space. Thankfully, with this much real estate available, containing the 7-inch 1280x800 60Hz LCD panel is not too much of a challenge.

The size of the machine also serves to house the complex controller set-up. Dual capacitive sticks (the machine knows when you're touching them) are paired with all of the controller inputs you'll find on a standard joypad, along with twin touchpads and programmable paddles on the rear of the unit. From a controller standpoint, the idea is to ensure complete compatibility with the PC library - an extension of the philosophy of the original Steam controller. Beyond that, it seems that every element of I/O from displays to peripherals is all routed through the USB-C port on the top of the machine, with the option to purchase an additional dock.

Valve Steam Deck Spec Analysis: Can It Really Handle AAA PC Gaming?

Note: Xbox Series S is arguably the baseline for 'next-gen' game development generally targeting 1080p at 60fps, so it is our chosen comparison point for Steam Deck, which aims for 720p/800p gaming. Power consumption was measured at 82.5W in Gears of War 5 on Series S. The 20W max power draw metric comes from Valve suggesting a minimum two-hour battery life from a 40WHr battery.

But really, the most interesting elements of Steam Deck are the semi-custom AMD processor and the background operating system - and we'll start with the first. Valve, via IGN, describes the chip as being next-gen in nature using the latest architectures - which is true, but only if we consider the consoles as the defining factor of what a generation actually is. You can effectively consider Steam Deck's chip as being most similar in nature to Xbox Series S, with significant reductions in all dimensions. The eight-core, 16-thread AMD Zen 2 chip is cut down by half, while the fixed 3.6GHz clock adjusts to a variable 2.4GHz to 3.5GHz. Series S's 20 RDNA 2 compute units drop down to just eight and again, a fixed clock on the Microsoft machine (1565MHz) shifts to a variable 1.0GHz to 1.6GHz on Steam Deck, meaning a range of 1TF to 1.6TF of GPU compute against the locked 4TF on Series S. Bearing in mind that we've measured Series S as drawing up to 82.5W of power, we need to keep expectations in check about the performance of Steam Deck.

Another key decision Valve has made about the specification of the unit concerns memory - 16GB of LPDDR5 rated at 5000 MT/s. Traditionally, graphics performance with AMD's APUs in the desktop space have been severely limited by memory bandwidth as opposed to compute. Games tend to gain more performance from plugging in faster RAM as opposed to overclocking the GPU itself. What Valve has come up with is a good solution for Steam Deck both in terms of available bandwidth (assuming Valve embraces something like a 128-bit interface to get the most out of it) and in the sheer amount of RAM available - anything less would have had severe consequences on the longevity of the system.

There are three Steam Decks available at $399/£349, $529/£459 and $649/£559. All that separates them at the internal hardware level is the amount of storage, while at the top level, anti-glare glass is added to the seven-inch LCD display (which peaks at 400 nits brightness). The base unit comes with a mere 64GB of eMMC NAND flash, while the higher level options ship with 256GB and 512GB NVMe drives respectively. According to Valve, the more space you opt for, the faster the read/write capabilities of the respective storage solutions. On top of this, a MicroSD slot is available to add additional space - but in loading time terms, performance here will very much come down to the quality of the card you insert. Personally, I'd strongly recommend either of the NVMe options over a NAND-based unit.

The hardware looks best-in-class for a handheld - and if Valve's intent is to deliver some level of competition to Nintendo Switch with its pricing, the value proposition is off the charts, relatively speaking. However, it is the software that has it all to prove. Steam Deck is effectively a PC as open as any other: there is nothing stopping you from installing Microsoft Windows or any other OS. However, that's not what the Deck ships with - what you're getting is an evolution of SteamOS, meaning that Linux is the primary operating system. This presents something of a problem in that actual native support for Linux is thin on the ground, while support for the preferable Vulkan graphics API is stronger but still far from taking root as the industry standard.

Valve's solution is a beefed-up version of Proton - a collection of technologies including WINE and DXVK that re-interpret Windows code to run on Linux. The ProtonDB database gives you some outlook on how good the technology is, but it's clear that 100 percent compatibility is not a given and you should expect a hit to performance compared to running natively on Windows. With that said, Steam is talking about a 'vastly improving Proton's game compatibility and support for anti-cheat solutions by working directly with the vendors.'

This is still the area where I'm cautious about Steam Deck's chances of fully delivering on the potential - the compatibility layer will need to be phenomenally good to get best performance from what is an excellent processor judged by mobile standards, but a rather weak one relative to a mainstream gaming PC. Questions also need to be asked about overall game performance - and we need to see much more from the system before we can offer any kind of definitive verdict. On the one hand, we've seen the device running challenging triple-A fare - running the full-fat PC rendition of Star Wars Jedi: Fallen Order on a mobile processor is no mean feat. Even more impressive than that is the split-second view we had of Remedy's Control running on the system. So, by extension, we can assume a very healthy level of performance for Steam Deck on the vast majority of PC titles in the Steam library, and let's not forget that we're talking about a catalogue of games here stretching back decades.

However, on the flipside, we have to think about the gaming generation to come. Let's not forget that Xbox Series S is considerably more power hungry and in its pursuit of 60fps for much of its library, dynamic resolution ranges are already hitting 720p minimums or even lower - and that's using a very low-level version of DirectX 12 built specifically for the silicon. Comparisons with Nintendo Switch also need to be treated with some degree of caution. On the one hand, there is no doubt that at the core specs level, Steam Deck is literally generations ahead in every dimension. But at the same time, comparisons between Switch and Nvidia Shield Android TV - built from the same silicon - show just how much extra performance is gained by having that direct low-level API access.

All of which leads us on to what I think is the key factor that could make or break Steam Deck - developer buy-in. Nintendo and Nvidia gave developers the tools and API to make Switch everything it could be, but fundamentally it's the game makers that tailored their code to the Tegra X1 processor. The list of so-called impossible ports for the Nintendo hybrid is immense, but the reason why they exist is because the time and effort was put in for this individual platform. So for Steam Deck, that's going to start with bespoke settings profiles that deliver a good experience for the hardware right from boot, with no further tuning from the user required - though of course, settings menus should remain.

But going forward, ensuring scalability is key to Steam Deck's future fortunes. Many existing techniques, such as temporal super-sampling and dynamic resolution scaling were existing technologies brought across from other console versions that proved crucial for Switch ports and I strongly suspect that Steam Deck is going to need them too to really be the best it can be. And if this leads to a stronger basis for scalability for PC ports in general, that can only be a good thing. Generally speaking, if the aim is to bring PC gaming more into the mainstream, the process of getting good out-of-the-box performance needs to be just as seamless as it is on consoles and to keep Steam Deck viable, more lower end options are going to be required for the latest games.

Beyond this, what also interests me about Steam Deck is the idea of PC gaming moving beyond the desktops and laptops into a whole new space - and with Nintendo having continuously proven the mainstream appeal of the mobile form factor, this is a bold move by Valve to say the least - especially in terms of pricing, which is very un-PC-like, and much more in line with console costs. But there's a key difference here and it's core to PC DNA - the idea that this is an entirely open platform.

Valve is clear that Steam Deck is a PC that you can do anything you like with, up to and including the installation of Windows - which may deliver improved performance on many games. It's also keeping SteamOS as open as it ever has been - the hope being that others will produce their own Deck-like devices. Whether they'll be able to match Valve's pricing seems unlikely in the short term, but with AMD and Intel processors improving all the time, along with the potential for improved screens, there may be scope for higher spec handhelds from independent manufacturers if the concept catches on.

In there here and now though, from my perspective, there are three key areas where Steam Deck has to prove itself. First of all, it's about the unit's functionality as a handheld. This thing is truly large: the ergonomics need to work, the screen needs to deliver and the battery life has to be decent. Secondly, compatibility is key: if Valve is talking about accessing your Steam library, that needs to just work - and that's where the apparently vast improvement in the Proton compatibility layer really needs to deliver. And finally, it's all about performance. The fundamentals are there to ensure that games run - but how well are they going to run? We are in a time of cross-gen transition in the industry: if the titles of today run fine, what about the games of tomorrow?