The NVIDIA GeForce GTX 1080 & GTX 1070 Founders Editions Review: Kicking Off the FinFET Generation
by Ryan Smith on July 20, 2016 8:45 AM ESTGP104: The Heart of GTX 1080
At the heart of the GTX 1080 is the first of the consumer-focused Pascal GPUs, GP104. Though no two GPU generations are ever quite alike, GP104 follows a number of design cues established with the past couple 104 GPUs. Overall 104 GPUs have struck a balance between size and performance, allowing NVIDIA to get a suitably high yielding GPU out at the start of a generation, and to be followed up with larger GPUs later on as yields improve. With the exception of the GTX 780, 104 GPUs been the backbone of NVIDIA’s GTX 70 and 80 parts, and that is once again the case for the Pascal generation.
In terms of die size, GP104 comes in at 314mm2. This is right in NVIDIA’s traditional sweet spot for these designs, slotting in between the 294mm2 GK104 and the 332mm2 GF104. In terms of total transistors we’re looking at 7.2B transistors, up from 3.5B on GK104 and the 5.2B of the more unusual GM204. The significant increase in density comes from the use of TSMC’s 16nm FinFET process, which compared to 28nm combines a full node shrink, something that has been harder and harder to come by as the years have progressed.
Though the density improvement offered by TSMC’s 16nm process is of great importance to GP104’s overall performance, for once density takes a back seat to the properties of the process itself. I am of course speaking about the FinFET transistors, which are the headlining feature of TSMC’s process.
We’ve covered FinFET technology in depth before, so I won’t completely rehash it here. But in brief, FinFETs are an important development for chip fabrication as processes have gone below 28nm. As traditional, planar transistors have shrunk in feature size – and ultimately, the number of atoms they’re comprised of – electrical leakage has increased. With fewer atoms in a transistor, there are equally fewer atoms to control the flow of electrons.
FinFET in turn is a solution to this problem, essentially allowing fabs to turn back the clock on electrical leakage. By building transistors as three-dimensional objects with height as opposed to two-dimensional objects, giving FinFET transistors their characteristic fins in the process, FinFET technology greatly reduces the amount of energy a transistor leaks. In practice what this means is that FinFET technology not only reduces the total amount of energy wasted from leakage, but it also allows transistors to be operated at a much lower voltage, something we’ll see in depth with our analysis of GTX 1080.
FinFETs, or rather the lack thereof, are a big part of why we never saw GPUs built on TSMC’s 20nm process. It was TSMC’s initial belief that they could contain leakage well enough using traditional High-K Metal Gate (HKMG) technology on 20nm, a bet they ultimately lost. At 20nm, planar transistors were just too leaky to use for many applications, which is why ultimately we only saw SoCs on 20nm (and even then they were suboptimal). FinFETs, as it turns out, are absolutely necessary to get good performance out of transistors built on processes below 28nm.
And while it took TSMC some time to get there, now that they have the capability NVIDIA can reap the benefits. Not only can NVIDIA finally build a relatively massive chip like a GPU on a sub-28nm process, but thanks to the various beneficial properties of FinFETs, it allows them to take their designs in a different direction than what they could do on 28nm.
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Ranger1065 - Thursday, July 21, 2016 - link
Your unwavering support for Anandtech is impressive.I too have a job that keeps me busy, yet oddly enough I find the time to browse (I prefer that word to "trawl") a number of sites.
I find it helps to form objective opinions.
I don't believe in early adoption, but I do believe in getting the job done on time, however if you are comfortable with a 2 month delay, so be it :)
Interesting to note that architectural deep dives concern your art and media departments so closely in their purchasing decisions. Who would have guessed?
It's true (God knows it's been stated here often enough) that
Anandtech goes into detail like no other, I don't dispute that.
But is it worth the wait? A significant number seem to think not.
Allow me to leave one last issue for you to ponder (assuming you have the time in your extremely busy schedule).
Is it good for Anandtech?
catavalon21 - Thursday, July 21, 2016 - link
Impatient as I was at the first for benchmarks, yes, I'm a numbers junkie, since it's evident precious few of us will have had a chance to buy one of these cards yet (or the 480), I doubt the delay has caused anyone to buy the wrong card. Can't speak for the smart phone review folks are complaining about being absent, but as it turns out, what I'm initially looking for is usually done early on in Bench. The rest of this, yeah, it can wait.mkaibear - Saturday, July 23, 2016 - link
Job, house, kids, church... more than enough to keep me sufficiently busy that I don't have the time to browse more than a few sites. I pick them quite carefully.Given the lifespan of a typical system is >5 years I think that a 2 month delay is perfectly reasonable. It can often take that long to get purchasing signoff once I've decided what they need to purchase anyway (one of the many reasons that architectural deep dives are useful - so I can explain why the purchase is worthwhile). Do you actually spend someone else's money at any point or are you just having to justify it to yourself?
Whether or not it's worth the wait to you is one thing - but it's clearly worth the wait to both Anandtech and to Purch.
razvan.uruc@gmail.com - Thursday, July 21, 2016 - link
Excellent article, well deserved the wait!giggs - Thursday, July 21, 2016 - link
While this is a very thorough and well written review, it makes me wonder about sponsored content and product placement.The PG279Q is the only monitor mentionned, making sure the brand appears, and nothing about competing products. It felt unnecessary.
I hope it's just a coincidence, but considering there has been quite a lot of coverage about Asus in the last few months, I'm starting to doubt some of the stuff I read here.
Ryan Smith - Thursday, July 21, 2016 - link
"The PG279Q is the only monitor mentionned, making sure the brand appears, and nothing about competing products."There's no product placement or the like (and if there was, it would be disclosed). I just wanted to name a popular 1440p G-Sync monitor to give some real-world connection to the results. We've had cards for a bit that can drive 1440p monitors at around 60fps, but GTX 1080 is really the first card that is going to make good use of higher refresh rate monitors.
giggs - Thursday, July 21, 2016 - link
Fair enough, thank you for responding promptly. Keep up the good work!arh2o - Thursday, July 21, 2016 - link
This is really the gold standard of reviews. More in-depth than any site on the internet. Great job Ryan, keep up the good work.Ranger1065 - Thursday, July 21, 2016 - link
This is a quality article.timchen - Thursday, July 21, 2016 - link
Great article. It is pleasant to read more about technology instead of testing results. Some questions though:1. higher frequency: I am kind of skeptical that the overall higher frequency is mostly enabled by FinFET. Maybe it is the case, but for example when Intel moved to FinFET we did not see such improvement. RX480 is not showing that either. It seems pretty evident the situation is different from 8800GTX where we first get frequency doubling/tripling only in the shader domain though. (Wow DX10 is 10 years ago... and computation throughput is improved by 20x)
2. The fastsync comparison graph looks pretty suspicious. How can Vsync have such high latency? The most latency I can see in a double buffer scenario with vsync is that the screen refresh just happens a tiny bit earlier than the completion of a buffer. That will give a delay of two frame time which is like 33 ms (Remember we are talking about a case where GPU fps>60). This is unless, of course, if they are testing vsync at 20hz or something.