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The case for 30fps PC gaming

Why frame-rate control is just as important as display resolution and quality presets.

Crysis 3 has so many performance bottlenecks that a 30fps lock produces a huge improvement on a vast range of gaming PCs.

Top-of-the-line enthusiast gaming PCs are built for raw performance, boasting technical specifications with far more horsepower than the Xbox One and PlayStation 4, opening up a wealth of gameplay options unavailable to console owners. If you fancy gaming at 2.5K, or 4K, at 60fps, 120fps or even higher, the PC is the only format with the flexibility and scalability to deliver. But that's not to say that the console-standard 30fps isn't a good fit for certain hardware specs, or specific titles. In a wealth of scenarios, limiting frame-rate can result in a markedly smoother gameplay experience. There's just one problem - only the tiniest minority of PC games actually offer the option to run at a locked 30fps.

Most PC games only have one frame-rate limiter available: turning v-sync on. This attempts to synchronise gameplay with the refresh rate of the display, in most cases limiting your system to 60fps. Out of the box, the only alternative is to disengage v-sync, allowing the game to run completely unlocked. There's no synchronisation with the display, meaning that frames are delivered as soon as the GPU finishes rendering them. This usually takes place as the screen is still refreshing, producing screen-tear, and a wholly inconsistent performance profile - input lag and visual feedback vary from moment to moment, often producing a sub-par experience.

Locking at 30fps is the solution often favoured by console developers - but why cut your potential frame-rate in half on a platform that offers so much flexibility? Why not settle on something like 40 or 45fps? The problem here is that 60 screen refreshes per second cannot be equally divided by 40 or 45 frames. Some frames stay on-screen for longer than others, resulting in off-putting judder. Locking to 30fps ensures that each rendered frame persists for two screen refreshes and presents with no screen-tear whatsoever. Combine that with a decent motion blur implementation and you have a good, consistent presentation. To find out more about why 30fps is sometimes the best option, check out our dedicated article that addresses the topic directly - do higher frame-rates always mean better gameplay?.

Put simply, there are plenty of good reasons why console developers choose to render their titles at 30fps and those reasons are equally valid for PC gaming. However, it doesn't answer the fundamental question - why not always target the full 60fps on your PC? Let's be clear here, it is the preferable option. However, we can think of a number of reasons:

1. Your PC isn't powerful enough

We've found that a Core i3 4130 CPU matched with an Nvidia GTX 750 Ti often manages to match or exceed PlayStation 4 performance on broadly equivalent quality and resolution settings - something we've experienced on releases like Call of Duty: Advanced Warfare, Assassin's Creed Unity and Far Cry 4 (with the no-stutter fix in place). These are entry-level enthusiast gaming PC components capable of producing a viable 'next-gen' console-style experience, but they will struggle to run cutting-edge games at 1080p60 on anything approaching max quality settings. Even dialling down graphics presets probably won't help owing to the limited power of the CPU - not everyone runs with the overclocked Core i7s that tend to be used in graphics card reviews. In our tests, artificially capping frame-rates to 30fps is the best solution for getting the most out of these budget-orientated parts, and we suspect that this applies to older PC gaming rigs too.

2. You have an extreme resolution screen

Driving higher resolution screens requires more intensive processing, demanding powerful graphics hardware. 2.5K - or 2560x1440 - represents a 78 per cent boost in pixel count over 1080p, while 4K is a gargantuan increase of 300 per cent. Even the fastest single-chip graphics card on the planet - the GTX 980 - can't run titles like a maxed Crysis 3 at 2.5K at a locked 60fps, let alone 4K. It's often the case that getting the best PC gaming experience is about choosing your compromises. If you're gaming on an extreme resolution display, you'll be dialling down quality presets to increase performance, and you're probably going to make further trades by lowering your frame-rate expectations. Capping at 30fps introduces a consistency here you won't get otherwise and it's a great option to have in your tweaking arsenal if you can't get close to the magic 60fps at your preferred settings.

3. Games can be CPU-bound, poorly optimised - or both

If an overclocked Core i7 working in combination with a top-end graphics card can't run certain games at a locked, consistent 60fps, we're in trouble. We've seen it recently with poor PC conversions like Dead Rising 3 and The Evil Within - they can hit 30fps just fine on a multitude of PCs, but hitting and sustaining 60fps seems unattainable, no matter how much in the way of GPU or CPU resources we throw at the title. In these situations, we can either dedicate system resources to a fluctuating performance level, or we can lock at 30fps and use our hardware to improve graphical quality, either through higher quality presets, running on higher resolution displays or using super-sampling on a standard 1080p screen. In short, on a platform where flexibility is its strongest asset, frame-rate control is another potential option in getting the best possible gaming experience from a particular title.

Of course, there's a reason why capping PC gameplay at 30fps isn't a more popular option - typically, very few games actually feature frame-rate limiting options, even when their console equivalents more often than not have 30fps caps in place. And when they do, often they don't work very well. In some cases, you get your 30fps, but frames are delivered in an uneven manner, arriving at 16ms, 33ms or 50ms intervals, producing obvious judder when v-sync is engaged. For a 30fps cap to work, it needs to deliver a new frame for every other screen refresh.

So how can you impose your own frame-rate limits on your games and make sure that new frames are evenly paced? There are a number of solutions out there, but we tend to stick to a brace of proven technologies. First of all, for Nvidia owners, the GPU control panel offers up a number of v-sync options - "half-rate adaptive" is the one you want. This imposes a console-style refresh onto your PC titles - games are locked at 30fps, but if render time exceeds the allotted 33.33ms per frame, you'll get some screen-tear until the problem area cleans up. This should only happen very rarely, assuming you are realistic with your quality settings.

In addition to the GPU control panel options, there's also the frame-rate limiter built into Riva Tuner Statistics Server, a FRAPS-like piece of software available as part of the MSI Afterburner overclocking package. This runs on any GPU, whether it's from AMD or Nvidia, and it's an essential tool for all PC gamers. It's worth pointing out that in some cases, you may require both pieces of software running in concert to get perfectly paced 30fps gameplay, but generally speaking we recommend using the GPU panel option first, as running both together may introduce conflicts in the system.

Crysis 3 on an overclocked 47 Pentium coupled with a sub-100 graphics card is a recipe for disaster at 1080p on high settings. Or is it? We achieved startlingly good results with this precise set-up with Nvidia's 30fps half-refresh adaptive v-sync in play.

Scalability vs 'cinematic' frame-rate locks

We've put together this piece for a number of reasons, mostly because a 30fps option isn't incorporated into the vast majority of PC games, and the other alternatives to 60fps gameplay - persistent judder and/or screen-tear - are not the way that we personally want to play our games. But of course, the key attraction of the PC platform is its flexibility and its innovation. If you don't mind the visual artefacts we aren't particularly fond of, that's absolutely fine. PC gaming is unique in that it gives you the power to game as you please - and there are some very good reasons why you may prefer an unlocked frame-rate. For example, we have to say that 30fps gaming using keyboard and mouse controls isn't very pleasant at all as a gameplay experience, but it works just fine for joypads.

Looking forward, new technologies like Nvidia's G-Sync and AMD's FreeSync offer up the potential to lock frame-rates wherever you want without the visual drawbacks. This technology works by forcing the display to refresh its image when the new frame is ready to be rendered, not at a fixed 60Hz. In motion, we can confirm that a locked 40 or 45fps does indeed produce a better experience than 30fps, once judder and tearing are removed from the equation. G-Sync monitors are the only solution on the market right now and they're expensive, but Samsung FreeSync display are due in Q1 2015, so hopefully competition will drive the prices down on this essential technology sooner rather than later.

To conclude, let's be clear here - this piece isn't about giving a free pass to poorly optimised titles (though it may help to get better results from them if all other options fail) and we have serious issues with the 'cinematic' gaming argument occasionally rolled out by developer and publishers. It may make sense to run at 30fps on a fixed console platform, but the whole point of PC gaming is that the ability to define the experience rests with the player, based on how he or she wants to play, based on the kit available. The notion of placing arbitrary software limits on a platform where scalability is its key asset makes absolutely no sense to us, and it's no mistake that this argument usually rolls out in tandem with poorly performing software. Instead, think of this as an additional, occasionally invaluable addition to your PC toolbox - an option used by console developers - and often for good reason.

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