Nvidia GeForce GTX 1080: Deep Dive

Graphics card refreshes happen annually, but entirely new architectures and manufacturing processes are rarer - and have a much bigger impact.

Nvidia's new GeForce GTX 1080 is the first card to be unleashed with its new Pascal architecture and 16nm FinFET manufacturing process, and it's a game changer - both literally and metaphorically.

GTX 1080: Under the Hood

That move to a 16nm process is a significant leap forward from the 28nm process that's been used for GPUs since the autumn of 2012. The move to 16nm means a move to FinFET transistors, which means Nvidia can build its transistors into layers, each with several fins attached - rather than the flat planes of old.

That means the wafers that are used to create graphics cores can be packed with more, smaller transistors. In effect, it allows Nvidia to do more with less.

The move to 16nm FinFET has allowed Nvidia to super-charge its Pascal architecture and the GP104 core that's been used to create the GTX 1080. The new architecture makes big gains when it comes to asynchronous computing, and the huge blocks that hold hundreds of stream processors have been halved in size for a finer and more precise delegation of tasks.

The new card deploys 7.2 billion transistors and 2,560 stream processors and has a core clock of 1,607MHz with a boost speed of 1,733MHz. It's got 8GB of memory that uses the new GDDR5X chips - a refreshed design that delivers 320GB/s of bandwidth. The entire unit is just 314mm2 in size.

That's a lot of numbers, but just compare them to the GTX 980.

Last year's flagship had 5.2 billion transistors and 2,048 stream processors alongside core and boost clocks of 1,126MHz and 1,216MHz. It had 4GB of standard GDDR5 memory that tops out at 224GB/s. And, despite it being less impressive in every department, it still required a 398mm2 piece of silicon.

Nvidia's "do more with less" philosophy extends to the price, too: third-party versions of the GTX 1080 will dip below £500, which is an excellent price for such huge power - hundreds less than you would have had to spend just a short while ago.

That said, don't be fooled into buying one of Nvidia's Founders Edition cards. These are reference models that cost £619 and they don't really bring anything extra to the table - you only get Nvidia's admittedly impressive physical card and the smug sense of being first in the queue.

Feature Presentation

Pascal doesn't just turbo-charge the hardware - it introduces several exciting software features. Many of these will make big changes to game development.

"Nvidia's 'do more with less' philosophy extends to the price, too: third-party versions of the GTX 1080 will dip below £500, which is an excellent price for such huge power"

One of the most intriguing is the fourth version of Nvidia's Polymorph Engine. The new addition here is called Simultaneous Multi-Projection, and it's designed to ease the workload for a variety of high-end tasks like 3D rendering and VR gaming. it works by condensing geometry workloads and mimicking the curvature of screens and lenses. That means the system doesn't render unnecessary pixels, which makes it workload more efficient.

Simultaneous Multi-Projection allows Pascal cards to run up to 16 different projections in parallel, and its uses are myriad - running a second screen alongside a VR headset, perhaps, or for running huge multi-monitor setups off a single card.

Elsewhere, Nvidia's architecture is compatible with DirectX 12. The latest version of Microsoft's graphics APIs introduced numerous reductions in driver overhead, and developers can now send their own command lists and buffers directly to the GPU - which allows developers far greater control over the hardware, with easier parallel computation possible.

DirectX 12 sits alongside other low-level APIs like Vulkan and AMD's recently-discontinued Mantle, and multi-GPU support is now easier. It sounds good, but it's worth bearing in mind that DirectX 12 has only really improved performance for AMD cards up until now - and in some games, Nvidia's results have actually slightly declined. This is something that needs to be considered, although new games and driver updates mean it's an ever-changing field.

Other new Pascal features impact on media. The Pascal architecture now supports 12-bit/10-bit HEVC decoding and 10-bit encoding, and it's got HDCP 2.2 for playing and streaming 4K media that's protected by DRM.

New Nvidia cards can also now use DisplayPort 1.4 and HDMI 2.0b to output.

There's also NVLink, which is a new bus that enables data transfer between the CPU and GPU at far higher speeds than PCI Express can offer.

Setting the Benchmark

There's no denying the huge impact of the GTX 1080 in games performance.

The GTX 1080 will handle any title at 1080p and 1440p, and 4K tests really illustrate the gulf between Nvidia's latest card and its predecessors. Take GTA V: at 3,840 x 2,160 the new card averaged 70fps - while the GTX 980 could only manage 44fps. The GTX 1080's Witcher 3 result of 42fps was almost twice as quick as last year's card.

The new Nvidia hardware even outpaces supposedly beefier cards. Its 57fps 4K average in Metro: Last Light is better than the GTX Titan X and GTX 980 Ti, which couldn't get beyond 42fps - and the GTX 1080 opened up similar gaps in Crysis 3 and Middle Earth: Shadow of Mordor.

AMD's current cards can't cope, either. The Radeon R9 Fury X is the beefiest GPU in its range, and it averaged 48fps and 32fps in Shadow of Mordor and Crysis 3. The GTX 1080 scored 64fps and 41fps in those games.

"theoretical tests also illustrate the GTX 1080's power. In 3D Mark Fire Strike's benchmark the new Nvidia card scored 17,177 points - almost 3,000 ahead of its nearest rival"

A caveat, though: AMD is readying new architectures for release over the next few months. It's starting with the mid-range, Polaris-powered Radeon RX 480, but more powerful cards will be unveiled shortly afterwards with the firm's Vega hardware.

Don't assume that these games are benchmark-friendly titles that will skew results, either - theoretical tests also illustrate the GTX 1080's power. In 3D Mark Fire Strike's benchmark the new Nvidia card scored 17,177 points - almost 3,000 ahead of its nearest rival.

The efficient Pascal architecture allows Nvidia to produce outstanding results while consuming less power. My test rig with a GTX 1080 peaked at a power consumption level of 309W - while the GTX 980 Ti and GTX Titan X both needed at least 330W. Several AMD cards also required far more electricity to churn out poorer benchmark results.

More efficient and cooler cards might not have a big impact on games development, but they allow for smaller cards, smaller systems and smaller electricity bills.

Development Impact

It's clear that the GTX 1080 is enormously powerful - and it's clear that this power will have a huge impact on development.

In one sense the impact of the new card and the Pascal architecture will be quite straightforward. The affordability and power of the GTX 1080 - and the forthcoming GTX 1070, which will be cheaper - will make 4K PC gaming more accessible. It'll also ensure that more PC gamers will be able to run top-tier titles at their most demanding graphics settings.

That's going to give developers more headroom to push things further: textures, lighting, particle effects, animation and engines themselves will all benefit from Pascal. Many PC games already look stonking, and new graphics architectures give developers a bucketload of new power to push things forward.

The potential is there to make games that are bigger and better than the market's best titles. With so many games effectively shared between PC and console, we can talk about titles for all those formats when we talk about new graphics architectures - and when affordable, specialised consoles can churn out something like Uncharted 4, I'm excited to see how much better PC games can become.

"That's going to give developers more headroom to push things further: textures, lighting, particle effects, animation and engines themselves will all benefit from Pascal"

The impact of Pascal won't just be felt on higher-resolution panels - the new cards will allow more games to work well on VR headsets, too. These new bits of gear are especially demanding as they use dual screens, and so have to simultaneously render a game twice. They've previously been the preserve of extremely powerful desktops.

Any way that VR's barrier to entry can be lowered is a good thing, especially when headsets like the Oculus Rift and HTC Vive cost hundreds on their own.

The debut of the GTX 1080 introduces Nvidia's brilliant new architecture, and it's going to be matched by new hardware from AMD's factory-fresh Polaris and Vega architectures. That's a good thing for gamers, because it gives developers more room to manoeuvre.

The Danger of Complacency?

Pascal provides extra headroom and, with it, a huge amount of opportunity - but it also provides an opportunity for complacency.

There might be more opportunity to push things further in the graphical department, but that won't happen if developers don't give proper attention to PC versions of their games.

It's not surprising that the PC sometimes gets the short end of the stick - after all, it's far trickier to develop for the PC, which has an essentially infinite number of hardware configurations when compared to a locked-down console. But, that said, it remains disappointing - and no-one wins if Pascal's extra power is merely used to paper over the cracks.

Unfortunately, this will continue to happen, with a new architecture not enough to banish old habits. It's not like bad PC ports are a surprise: GTA IV was plagued by frame rate issues, Dark Souls arrived locked to 720p, and the Batman and Assassin's Creed franchises are infamous for arriving in awful states on PC.

What Comes Next?

We've established that the GTX 1080 is a monster, and that bodes well for other Pascal cards. Unfortunately, right now, we can only talk about one other Pascal-based product: the GTX 1070.

It's based on the same GP104 core as the GTX 1080 and uses the same number of transistors - to form this card, Nvidia simply deactivates some of its processing cores, so the GTX 1070 has 1,920 stream processors rather than the 2,560 of the GTX 1080.

The GTX 1070's core clock of 1,506MHz is a tad lower than the range-topping GTX 1080, too, and the more affordable card has regular GDDR5 memory rather than GDDR5X RAM. There's still eight gigabytes of it, but it's clocked a little slower and delivers less bandwidth.

The GTX 1070 won't be as fast as the GTX 1080, but it'll still be a fearsome GPU. If it maintains the rough 30% performance improvement over its predecessor, that means Nvidia will deliver a card which will easily handle any game at 1440p - and one that should run plenty of titles at 4K. With prices likely to come in at around £350, that's tempting.

Sadly we don't know anything about other Pascal cards, but if Pascal's impressive form continues then they're sure to be decent.

There's a slim chance that Nvidia's low-end 10-series cards won't use Pascal at all. Nvidia an AMD both have form when it comes to recycling and rebranding older architectures in new ranges.

"I'd usually expect AMD to fight back with its own high-end graphics cards, but the red team is diverging this year - and that means it'll be a little while before high-end Pascal cards see some direct competition"

It makes business sense - there's no need to deploy a new core when last year's gear will do the job - but it's worth bearing in mind if you're shopping at the low end.

Will AMD Fight Back?

I'd usually expect AMD to fight back with its own high-end graphics cards, but the red team is diverging this year - and that means it'll be a little while before high-end Pascal cards see some direct competition.

Instead, AMD is debuting its new Polaris architecture with more modest mid-range cards. It moves to a new 14nm FinFET architecture and concentrates on energy efficiency with a maximum 2,304 stream processors - and a design that'll handle 1440p games at 60fps.

The only Polaris card revealed so far is the RX 480, but no details have been emerged - just the fact that it'll cost less than $200 and be VR-capable.

You'll have to wait a little longer for AMD's high-end response to Pascal. That's coming from Vega, which will be launching at the end of 2016 or the start of 2017. It's likely to deploy a mighty 15 billion transistors, 4,096 stream processors and up to 32GB of memory - which means that AMD's next top-tier cards are likely to be monsters.

Conclusion?

Nvidia's latest graphics card release is a huge step forward in several important areas.

The new architecture doesn't just give developers a huge amount of power to play with at the top end - it'll trickle down to benefit everyone who uses cheaper cards, too. And Nvidia has locked and loaded Pascal with several impressive new features.

There's a lot here to excite developers; after all, this is one of the biggest changes in PC graphics in some years. The next step is to see how Pascal develops and how AMD responds - and we can't wait.