The GM204 GPU (which lies behind both the 980 and the 970) is the culmination of a process that started many months ago, with the GTX 750 Ti. As an overall package, we didn’t really rate the 750 Ti. While it generated a very impressive amount of speed given its low power output, in terms of realworld performance it offered customers very little they couldn’t get from existing products at a similar price point. We could, though, see where the company was going with the GM204. (See all graphics cards and components reviews.) With its ultra-efficient design, the GM204 clearly had room to expand and create very powerful gaming equipment for a modest power outlay. And the 980 and 970 are the spectacular proof. So let’s start by taking a closer look at what the new GPUs offer.
NVidia GTX 980 vs NVidia GTX 970 comparison: Smaller is Better – Or is It?
Like the older Kepler range, the Maxwell GPUs are constructed using a 0.28nm manufacturing process. We would generally expect this process to have shrunk in size by now, as the number typically falls every two years, producing smaller and more efficient designs that generate less heat, and which can be pushed to higher power levels. Unfortunately, the two-year cycle has been held up this time round, which is partly why nVidia has worked so hard on streamlining the way the technology itself works. It’s rather like a town that has consistently expanded in size every two years for over a decade. If the town temporarily runs out of expansion space, the planners have to work instead on making the town itself work better, redirecting traffic more efficiently, and allowing the flow to continue unimpeded. The key to this reorganisation is the enhanced SMM (Streaming Multiprocessor Maxwell). The older Kepler GPUs already made use of the cleverly tweaked SMX (Streaming Multiprocessor neXt generation), but SMMs take this to a whole new level. Each individual SMM is much smaller, meaning that instructions can be handled with greater efficiency. Inevitably, though, this means that single SMMs are armed with fewer weapons than their SMX counterparts. So whereas a standard SMX, for instance, contains 192 shader cores, the humble SMM contains just 128. There’s a knock-on effect on texture units too, with each SMM offering a mere eight of these, against the 16 of the SMX.
The first Maxwell-equipped product we looked at, the 750 Ti, came with five SMMs enabled. These allowed it to offer 640 shader cores and 40 texture units. In contrast, the 970 and 980 are considerably beefed up, with 13 and 16 SMMs switched on respectively. So that gives the 970 1664 shader cores, and 104 texture units, while the 980 has 2048 shader cores, and 128 texture units. The 980, as you would expect, has more of both, although the differences are not massive, given the price jump. It’s also notable that both chips pale next to the figures boasted by, for example, the GTX 780 Ti. The latter’s 15 bumper-packed SMXes ultimately add up to far bigger numbers, with a rather massive complement of 2880 shader cores and 240 texture units – the 780 Ti costs a similar price to the 970, but has 73% more shader cores and 130% more texture units overall. Luckily, Maxwell is about far more than simple firepower. Compared to SMXes, SMMs will have to share far fewer resources with one another. And while it’s no surprise to find both the 970 and 980 armed with 4GB of GDDR5 RAM as default – their predecessors often went up to no more than 3GB – the L1 and L2 caches have been considerably bolstered. The shared memory now stands at 96KB for every SMM, and the Kepler’s 512KB L2 cache has been quadrupled in size to a 2MB version in the 970 and 980. These ultra-fast forms of memory can now be used more efficiently and more consistently by Maxwell, so there should be fewer blockages and faster flow as a result. Again, the 980 has a small advantage here, although the 970 is hardly crippled in contrast. See all PC Components and Upgrades reviews.
NVidia GTX 980 vs NVidia GTX 970 comparison: Memory Bandwidth
You might expect the 980 and 970 to offer strong memory bandwidth. Unfortunately, the 384bit memory bus offered by the earlier GTX 780 Ti has been reduced to a 256bit version in the case of both the 980 and 970. However, Maxwell does have one slick trick up its pipline – the Third Generation Delta Color Compression. This concept has been seen in AMD products before, but is relatively new to the mainstream nVidia products, and uses compression to allow the memory bus to process more data without causing a bottleneck. The end-result is that the new cards’ 256bit memory interface proves not to be the bar to high-performance that you’d think it to be. (See also: NVidia GTX 970 vs NVidia GTX 780 Ti vs AMD Radeon R9 290X comparison.)
The main idea behind Maxwell is that it does rather more with considerably less. As such, it doesn’t perhaps fare well in terms of raw figures. That’s particularly so when we look at memory bandwidth calculations. The standard GTX 980 and GTX 970 both come with memory clocks of 1.75GHz (effectively 7GHz when you take into account the quadrupling properties of the RAM). Those 7GHz speeds place them on a par with the 780 Ti. However, the 256bit memory buses of the 980 and 970 push them back on paper, leaving them both with memory bandwidth figures of 224GB/sec. In comparison, the 780 Ti comes with a gargantuan bandwidth figure of 336GB/sec. Of course, as we’ve already noted, the 980 and 970 use special compression to optimise the memory bandwidth, and those effects won’t be reflected in the raw figures. So we’ll have to reserve judgement for now. It’s interesting, though, that nVidia have made so little attempt to differentiate the 980 and 970 here, with both having essentially identical bandwith figures.
NVidia GTX 980 vs NVidia GTX 970 comparison: Clock Speeds and Textures
One of the beauties of Maxwell’s smaller and more efficient Streaming Multiprocessors is that they can be pushed to higher clock speeds. Using Boost, the standard GTX 980 and 970 can reach core clock speeds of 1216MHz and 1178MHz respectively. This is clearly much higher than the GTX 780 Ti’s 928MHz. Once more, though, the 980 is only marginally superior to the 970. And that extra firepower doesn’t help everywhere, with the older 780 Ti arguably proving the better card at handling textures, by dint of having greater quantities of texture units. The 980 has a relatively healthy 128 of these, and the 970 falls some way behind with 104. The 970’s figure, in particular, is poor when you compare it to the older 780 Ti’s 240 texture units. However, neither new Maxwell chip fares brilliantly here. Unsurprisingly, the 980’s texture fill rate of 155.6GT/sec rather destroys the 970’s 122.5GT/sec, but both lag some way behind the 780 Ti’s astonishing figure of 222.7GT/sec. Again, the raw results probably don’t do justice to Maxwell’s heavily fine-tuned architecture. But we’ll have to wait and see whether these chips can overhaul the on-paper advantage of the previous generation.
NVidia GTX 980 vs NVidia GTX 970 comparison: Low in Power but High in Choice
But before we dive into the realworld results, why would nVidia want to turn out technology that, on paper at least, seems so inferior to the flagships of the previous generation? Well, Maxwell does have one very obvious advantage. And that comes from the power output. The TDP (Thermal Design Power) figure gives us an indication of how much power a system is likely to have to cope with, when using this card. The lower the better. The GTX 970 comes with an incredbly modest TDP of 145 watts. As a point of comparison, even the mid-range GTX 760 came with a TDP of 170 watts, so the GTX 970 is extremely low on power consumption for a product that can produce this level of performance. Perhaps even more astonishing, though, is the 980, which comes with a TDP of 165 watts – still lower than that aforementioned GTX 760. This is an incredible achievement, and is put very much into perspective by the corresponding figures for the GTX 780 Ti and Radeon R9 290X, which measure 250 and 300 watts respectively! In practise, we found that the Maxwell cards weren’t quite as modest on power as this might suggest. But under load, the R9 290X was generating around 72 watts more than the 980, which was itself around 17 watts higher than the 970.
NVidia GTX 980 vs NVidia GTX 970 comparison: Benchmark Tests
All the hardware advantages in the world won’t help you, though, if the realworld performance isn’t there. How do these cards really operate? To find out, we’ve pitted them against one another across four different games, taking in default settings, and three separate resolutions. For the sake of comparison, we’ve set them against the figures of the Kepler-equipped 780 Ti.
As you might expect, the 980 is the superior card, commanding a lead of 15fps over the 970 at 1900×1200. The gap has fallen to 9.5fps by the time we reach a resolution of 3840×2160, although as a percentage of the frame rate, this is actually a bigger lead for the 980. The 780 Ti is a little faster than the 970, but still 9.4fps down on the 980 at the lowest resolution, and 6.3fps behind at the highest level. Again, the 980 is very much in charge at 1920×1080, leading the 970 by 15.4fps. However, the lead is a mere 6.1fps at 3840×2160. The 780 Ti is even closer by this point, finishing just 4.3fps behind the 980, and 1.8fps ahead of the 970. However, at the lowest resolution, it trails the 980 by 11.8fps, and leads the 970 by as many as 3.6fps. The 980 retains a double-digit lead over the 970 all the way through, although the gap remains almost identical throughout, tallying 10.4fps at the lowest 1900×1200 resolution, but rising merely to 10.5fps at 3840×2160. Again, though, viewed as a percentage, this is a significantly increased lead, given that the frame rates have almost halved at this point. The 780 Ti trails the 980 by 7.9fps at 1900×1200, and by 6.4fps at 3840×2160. It has a smaller though decisive lead over the 970, finishing 2.5fps ahead at 1900×1200, and 4.1fps at 3840×2160. In our final set, the 980 achieves a lead of 11.5fps over the 970 at 1920×1080, and this falls to 6.5fps at 3840×2160. The 780 Ti has a smaller 1.4fps lead over the 970 at 1920×1080, and this increases to a still fairly minor 2.4fps at 3840×2160. However, even the mighty 980 isn’t very far ahead, recording a lead over the 780 Ti at the lowest resolution of 9.1fps, and seeing this fall to 4.1fps at 3840×2160. This is a fairly difficult set of tests, and the overall figures are so low that there isn’t that much variation between the three cards.
NVidia GTX 980 vs NVidia GTX 970 comparison: Verdict
So do you go for a 980 or a 970? Well, the 980 is the best single-GPU solution out there (watch out for more high-end comparisons), and will provide you with as much power as you need from one card. In terms of benchmarks, the 970 seems rather disappointing. However, it’s worth bearing in mind that the 970 could cost you £150 or more less. For typical gamers, the 970 will more than suffice, and is a better alternative to the Radeon R9 290X. Don’t discount the 780 Ti, as this is faster than the 970, and can be bought for only a small amount extra. However, assuming that one becomes unavailable, the 970 is the best mid-price option. For more hardened players with plenty of money, the 980 is the one to really set their sights on, and will give them the best single-GPU card on the market.
NVidia GTX 980 vs NVidia GTX 970 comparison: Available Cards
£430 – Inno3D GeForce GTX 980 Herculez X3 Ultra – 4GB, Core Clock 1,152MHz (1,253MHz Boost), Memory Clock DDR Effective 7010MHz, 2yr Warranty £430 – GALAX GeForce GTX 980 SOC Gamer – 4GB, Core Clock 1,127MHz (1,216MHz Boost), Memory Clock DDR Effective 7010MHz, 2yr Warranty £440 – MSI GeForce GTX 980 Gaming Edition 4096MB – 4GB, Core Clock 1,216MHz (1,317MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty £450 – Palit GeForce GTX 980 JetStream – 4GB, Core Clock 1,127MHz (1,216MHz Boost), Memory Clock DDR Effective 7010MHz, 2yr Warranty £456 – Gigabyte GeForce GTX 980 Reference Design – 4GB, Core Clock 1,127MHz (1,216MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty £480 – Zotac GeForce GTX 980 AMP Omega Edition – 4GB, Core Clock 1,202MHz (1,304MHz Boost), Memory Clock DDR Effective 7046MHz, 5yr Warranty £500 – Asus GeForce GTX 980 DirectCU II OC Strx – 4GB, Core Clock 1,178MHz (1,279MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty £500 – EVGA GeForce GTX 980 Superlock ACX 2.0 – 4GB, Core Clock 1,266MHz (1,367MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty Verdict – Of the cheaper cards, the MSI seems to be the best choice. Only £10 off the bottom tag, it nonetheless has a Boost of 1317MHz, giving it a very significant advantage over the 1216MHz of the standard cards. For ultimate power, the EVGA version goes right up to 1367MHz, although the MSI is better value. £276 – GALAX GeForce GTX 970 EX OC – 4GB, Core Clock 1,126MHz (1,266MHz Boost), Memory Clock DDR Effective 7010MHz, 2yr Warranty £276 – Inno3D GeForce GTX 970 OC – 4GB, Core Clock 1,088MHz (1,228MHz Boost), Memory Clock DDR Effective 7010MHz, 2yr Warranty £290 – Palit GeForce GTX 970 JetStream – 4GB, Core Clock 1,152MHz (1,304MHz Boost), Memory Clock DDR Effective 7010MHz, 2yr Warranty £294 – MSI GeForce GTX 970 Gaming Edition – 4GB, Core Clock 1,140MHz (1,279MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty £308 – Zotac GeForce GTX 970 AMP Omega Edition – 4GB, Core Clock 1,102MHz (1,241MHz Boost), Memory Clock DDR Effective 7046MHz, 5yr Warranty £308 – EVGA GeForce GTX 970 SC ACX 2.0 – 4GB, Core Clock 1,165MHz (1,317MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty £312 – Asus GeForce GTX 970 DirectCU II OC Strix – 4GB, Core Clock 1,114MHz (1,253MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty £320 – Gigabyte GeForce GTX 970 G1 Gaming – 4GB, Core Clock 1,178MHz (1,329MHz Boost), Memory Clock DDR Effective 7010MHz, 3yr Warranty Verdict – With this card, the key is very much getting value, and the £290 Palit offers plenty of power (a 1304MHz Boost clock) for its modest price. You can get an extra 25MHz from the £320 Gigabyte, but there’s no need to pay more than £290-£294 for the impressive Palit and MSI versions. See all graphics card reviews.
