GeForce GTX 460 SLI vs. Radeon HD 5970: Two Against One

After the launch of GF104 Nvidia got a real opportunity to design a dual-processor graphics card with Fermi architecture that would offer acceptable thermal and electrical specs. Our today’s article will discuss the performance of a solution like that.

by Alexey Stepin , Yaroslav Lyssenko
08/20/2010 | 01:29 PM

As you know from our news and reviews, AMD’s superiority in the sector of single-processor gaming graphics cards has been challenged by Nvidia releasing its GeForce GTX 480, yet the AMD Radeon HD 5970 is still unrivalled as the best dual-chip solution, carrying two RV870 Cypress processors on board. The GeForce GTX 480 fails to compete, largely due to its lower texture-mapping performance, but AMD’s solution is superior to its opponent in the rest of technical specifications, too. However, there is not doubt Nvidia wants to challenge AMD here as well, so the development and release of a dual-processor card with Fermi architecture is just a matter of time and technical ability.

 

Nvidia had serious technological obstacles until recently because the hypothetic dual-processor GeForce GTX 490/495 would turn out to be too hot and power-consuming even if based on a GeForce GTX 470 SLI configuration, let alone GTX 480 SLI. So, although a pair of GeForce GTX 470 cards working in SLI mode could deliver the desired performance, the GeForce GTX 490/495 was still not feasible. But now that Nvidia has its new, simpler and more economical GF104 core, the situation is completely different. This rather inexpensive GPU is a much better building block for a dual-chip gaming graphics card than the monstrous GF100. Our tests showed it to be competitive to the GeForce GTX 470 at increased clock rates, and a pair of GF104 chips in a SLI tandem looks impressive even at the reference frequencies:


Click to enlarge

The hypothetic GeForce GTX 490/495 is going to be slower if based on GF104 cores than if it were equivalent to the GeForce GTX 470 SLI configuration. On the other hand, it will be faster than the single GeForce GTX 480 while costing the same or less money and will also be good in comparison with the Radeon HD 5970, being only inferior to the latter in terms of texture-mapping performance, which is the common problem of all Fermi-based solutions. When developing its Fermi architecture, Nvidia enhanced the GPU’s geometry-processing resources at the expense of texture-mapping ones. Practice suggests that this doesn’t prevent GF100- and GF104-based graphics cards from doing well in today’s games and their advanced tessellation units are going to be most helpful in the next generation of games that will use a lot of tessellation.

A dual-GF104 card may make the GeForce GTX 480 unpopular if comes at a comparable price but it’s too early yet to make any predictions about that, especially as GF100-based solutions have a reserve of untapped resources and can get faster if all the 512 stream processors are enabled in them.

It is certain, though, that this variant is going to be cheaper than a dual-GF100 solution and AMD will have to cut its prices because the Radeon HD 5970 is still hard to find at its recommended price of $599. Most offers are in the range of $630-650, but sometimes this card may be priced at $700 and more. Of course, a $500 GeForce GTX 490/495 cannot bring in much profit, just as any other premium-class graphics card for that matter, but its release may boost Nvidia’s reputation and popularity among demanding gamers who don’t want to bother about building discrete SLI or CrossFire tandems. So, we can expect a graphics card with two GF104 cores working in their full configuration with 384 stream processors and 64 TMUs; it may be called GeForce GTX 495. The name of GeForce GTX 490 may be given to the same solution based on two cut-down GF104 cores.

It is the latter variant that we are going to test today using a couple of GeForce GTX 460 1GB cards in SLI mode. One of the components of this tandem is a Zotac GeForce GTX 460 1GB (ZT-40402-10P). Let’s have a closer look at it now.

Zotac GeForce GTX 460 1GB

Packaging and Accessories

Zotac’s retail product boxes do not come in many shapes or original designs. Their advantage is in the window through which you can have a look at the graphics card without taking the latter out. You can see what the graphics card is like before purchasing it.

Besides the basic product information and the mention of Zotac’s extended warranty, there is a sticker on the box telling you that a copy of Prince of Persia: The Forgotten Sands is included with the graphics card.

There is a foam-rubber tray inside with cutouts for the card and its accessories. The graphics card is fixed securely in its place and protected against any hazards that might occur during its transportation and storage (not against serious hazards, though). The Zotac GeForce GTX 460 1GB comes with the following accessories:

There is everything you need to use the card plus a copy of a new game from the Prince of Persia series. The free game is a nice surprise since few graphics card makers include such free stuff with their products nowadays.

Thus, we don’t have any complaints about the way the Zotac GeForce GTX 460 1GB is packaged and complemented with accessories. Now let’s take it out of the box and have a closer look at it. By the way, it is the first GeForce GTX 460 1GB we see that is based on the reference design developed by Nvidia.

PCB Design and Specifications

The reference GeForce GTX 460 1GB resembles all recent top-class products from Nvidia as it uses a cooling system with blower that exhausts the hot air out of the system case.

The card looks heavier than the Gainward GeForce GTX 460 GS GLH we reviewed earlier and is longer. Not much longer, though, so the Zotac can be installed into most system cases easily. You may only have problems connecting the power cables in a short chassis: as opposed to the Gainward card, the Zotac has its power connectors at the shorter edge of the PCB rather than at the top edge.

The component layout resembles that of the above-mentioned Gainward. One of the memory chips is placed separately from the others, next to the DVI connectors. The power circuit is designed like 3+1, the 3-phase GPU voltage regulator being controlled by an NCP5388 chip from ON Semiconductor. The same controller is used in GeForce GTX 470 and 465 cards.

The MSI Afterburner tool supports this chip but the top limit for the GPU voltage is 1.087 volts. This limitation can only be removed by using a modified BIOS but our attempt to do so failed and we had to restore the original BIOS. An Anpec Electronics APW7165 chip is responsible for powering the graphics card’s memory. We saw it before, for example on the GeForce GTX 465. Like the Palit version, the reference GeForce GTX 460 receives external power via two 6-pin PCIe 1.0 connectors.

The card is equipped with K4G10325FE-HC05 memory chips from Samsung Semiconductor that have a capacity of 1 Gb (32 Mb x 32) and a rated frequency of 1000 (4000) MHz. As opposed to the Gainward GeForce GTX 460 1GB GS GLH, the card has the reference memory frequency of 900 (3600) MHz. This is not high, at least in combination with its 256-bit memory bus, compared to AMD’s solutions. The total amount of onboard memory is 1024 megabytes, which is enough for any modern application or game. The card can lower its memory frequency to 324 (1296) MHz and to 135 (540) MHz depending on the running application: the former mode is for video playback and the latter is for 2D office applications. The Zotac is no different from the Gainward GeForce GTX 460 1GB GS GLH in this respect.

Our Zotac GeForce GTX 460 1GB has an A1 revision GF104 chip manufactured on the 23rd week of 2010. The GPU works in its maximum configuration available today: 336 ALUs, 56 TMUs and 32 RBEs. The card has the reference GPU clock rates: 675 MHz for the main domain and 1350 MHz for the shader domain. The GPU frequencies are lowered to 405/810 MHz and 51/101 MHz in the two power-saving modes. The core voltage in 3D mode is 0.987 volts. It lowers to 0.912 and 0.875 volts in the first and second power-saving mode, respectively. As we wrote above, the highest voltage you can set with software tools is 1.087 volts. You have to modify the card’s BIOS to achieve higher values. The current version of GPU-Z still reports the parameters of GF104-based cards incorrectly, particularly the number of active shader processors. You shouldn’t worry about the number 224 reported by this tool. It doesn’t mean that the graphics card is defective. In fact, the card has 336 active ALUs (out of the total of 384 which are physically present in the GPU).

Nvidia’s reference sample has a more up-to-date set of interfaces than the Gainward card. It has every popular digital interface, including DisplayPort, and supports D-Sub via an adapter. There is one MIO connector for uniting two GeForce GTX 460s into a SLI tandem. The Zotac card worked without any problems in SLI mode during our tests.

The reference cooling system of the GeForce GTX 460 is simple and not new, tracing its origin from the GeForce 8800 GTX’s cooler. However, it uses direct-touch technology, which means that the heat pipes have direct contact with the GPU’s heat-spreading cap. We’ve already seen this technology in the coolers of GeForce GTX 480, 470 and 465 series cards. Oddly enough, there are no thermal pads for the memory chips and power system components.

You can read the fan marking in the photo. The Protechnic MGT8012YB-W20 model is well known to everyone who prefers Nvidia products because this fan is installed into most reference coolers from Nvidia. Depending on its speed, the fan can be anything from very quiet to as loud as a vacuum cleaner.

The heatsink is rather small and its heat dissipation area isn’t large, especially in comparison with the cooler installed on the Gainward card. Yes, it should cope with the GF104 well enough, yet we do not expect a low temperature. We’ll check this out in the next section of this review but we guess the GeForce GTX 460 calls for a more serious heatsink. We are also skeptical about the two-tier placement of the DVI connectors. The result is that there are fewer vent holes in the card’s mounting bracket for the cooling system to exhaust the hot air. You’ll learn how this affects the card’s cooling in the next section of our review.

Power Consumption, Temperature, Noise, Overclockability

We used a nonstandard GeForce GTX 460 1GB to measure the power consumption of GF104-based solutions in our earlier tests, so now we want to recheck the results using the Zotac card and our testbed configured like follows:

The new testbed for measuring electric characteristics of graphics cards uses a card designed by one of our engineers, Oleg Artamonov, and described in his article called PC Power Consumption: How Many Watts Do We Need?. As usual, we used the following benchmarks to load the graphics accelerators:

Except for the maximum load simulation with OCCT, we measured power consumption in each mode for 60 seconds. We limit the run time of OCCT: GPU to 10 seconds to avoid overloading the graphics card's power circuitry. Here are the obtained results:

The graphics cards from Nvidia and Palit/Gainward behave in a similar way in desktop mode, having a peak power consumption of 20 watts. And then they differ. Particularly, the reference card has a higher peak power draw when performing such not very heavy tasks as decoding HD video. When it switches into power-saving mode with reduced clock rates, its average power consumption is about 23 watts, which is comparable to the results of the Gainward card, but the latter is quicker to switch to save power.

The reference card from Nvidia also needs more power in modern games but the difference is less than 10 watts and can be neglected. Take note that the first power connector is loaded more than the second one: 7.4 and 3 amperes, respectively. So, the GeForce GTX 460 might have been even equipped with only one 8-pin PCIe 2.0 power connector (with a load capacity of 150 watts), but not all power supplies, especially in the midrange segment, offer them.

Thus, we don’t see anything new in our second test of the power consumption of the GeForce GTX 460 1GB. Its results are quite acceptable for its performance although inferior to same-class solutions from AMD.

Nvidia’s reference cooler is less effective than the cooling system installed on the Gainward/Palit card. This might have been expected, considering the smaller heatsink and the DVI connectors getting in the way of the hot air being exhausted out of the system case. On the other hand, the card was absolutely stable even under very hot weather. The reference cooler is going to be just fine for ordinary users who don’t intend to overclock the card. Otherwise, you need something better.

Considering the above-mentioned downsides of the reference cooler, the GeForce GTX 460 1GB is expectedly loud. It is as loud as the flagship GeForce GTX 480 in 3D mode and not silent in 2D mode, either. Granted, the weather was hot, but Gainward released a much quieter version of this card with higher GPU clock rates, so that’s not an excuse. If you value silence, you may want to replace the reference cooler or even buy a GeForce GTX 460 with a nonstandard and better cooler.

As for overclockability, the GPU of our Zotac GeForce GTX 460 1GB was stable at 820/1640 MHz and its memory, at 1065 (2130) MHz. This is somewhat higher than what we achieved with the Gainward GeForce GTX 460 GS GLH. The difference of 20 MHz wasn’t worth benchmarking the card once again in overclocked mode whereas our readers already know how fast the GF104 is at 800/1600 MHz. So, we will just focus on our main subject which is to benchmark the GeForce GTX 460 1GB in SLI mode.

Testbed and Methods

We are going to investigate the gaming performance of our GeForce GTX 460 SLI configuration using the following universal testbed:

The ATI Catalyst and Nvidia GeForce graphics card drivers were configured in the following way:

ATI Catalyst:

Nvidia GeForce:

Below is the list of games and test applications we used during this test session:

First-Person 3D Shooters

Third-Person 3D Shooters

RPG

Simulators

Strategies

Semi-synthetic and synthetic Benchmarks

We selected the highest possible level of detail in each game using standard tools provided by the game itself from the gaming menu. The games configuration files weren’t modified in any way, because the ordinary user doesn’t have to know how to do it. We updated our test modes and ran our tests in the following resolutions: 1600x900, 1920x1080 and 2560x1600. Unless stated otherwise, everywhere, where it was possible we added MSAA 4x antialiasing to the standard anisotropic filtering 16x. We enabled antialiasing from the game’s menu. If this was not possible, we forced them using the appropriate driver settings of ATI Catalyst and Nvidia GeForce drivers.

Besides GeForce GTX 460 SLI tandem, we have also tested the following solutions:

Performance was measured with the games’ own tools and the original demos were recorded if possible. We measured not only the average speed, but also the minimum speed of the cards where possible. Otherwise, the performance was measured manually with Fraps utility version 3.1.2. In the latter case we ran the test three times and took the average of the three for the performance charts.

Performance in First-Person 3D Shooters

Aliens vs. Predator

This game is benchmarked in DirectX 11 mode with the highest graphics quality settings.

The new tandem takes a good start, outperforming the GeForce GTX 470 SLI at every resolution, obviously due to its higher GPU clock rates. The difference is not large, but suggests that Nvidia’s next dual-processor graphics card is going to be indeed based on two GF104 chips. The GeForce GTX 460 SLI is fast enough to play at 1920x1080 but not at 2560x1600 although flagship graphics solutions are supposed to unlock such extremely high display modes.

Battlefield: Bad Company 2

Of course, the pair of GF104 chips finds it hard to compete with the pair of GF100s, even cut-down GF100s, especially when high clock rates can’t save the day. However, they are not lagging too far behind, so a dual-GF104 card would be a viable product capable of delivering a playable frame rate at 2560x1600 (or 2560x1440) at the maximum graphics quality settings.

Call of Duty: Modern Warfare 2

The GF104-based SLI tandem behaves like an ordinary GeForce GTX 480 here and is but slightly slower than the pair of GeForce GTX 470s working in SLI mode. In other words, there is no reason to run this game on a premium-class dual-processor graphics subsystem because a fast single-processor card, like a Radeon HD 5870, should be quite enough. Even the single GeForce GTX 460 1GB copes with the game, although there is no reserve of speed at 2560x1600.

Crysis Warhead

The GeForce GTX 460 SLI subsystem fails where least expected. We mean very high resolutions. Its average frame rate is comparable to that of the single GeForce GTX 480 but its bottom speed is only half the latter’s. Our hypothetic GeForce GTX 490 feels much better than the Radeon HD 5970 at resolutions up to 1920x1080, though.

Far Cry 2

As opposed to Crysis, the GeForce GTX 460 SLI looks good compared to the Radeon HD 5970 in Far Cry 2 even at 2560x1600. There were no image quality problems or anything; the gameplay was smooth even in the most complex scenes. Well, Far Cry 2 is not a heavy application anymore.

Note also that the gap from the GeForce GTX 470 SLI is very small which means we are unlikely to see dual-GF100 cards (unless ASUS releases a limited edition of yet another unique monster), but a dual-GF104 card, especially with all of the 384 shader processors unlocked, is going to be a competitive solution.

Metro 2033

This game is tested without multisampling antialiasing as it worsens the textures and provokes a performance hit.

The Radeon HD 5970 is in the lead in Metro 2033, especially at a resolution of 2560x1600, unless you turn on tessellation which wouldn’t be conspicuous in the dark post-apocalyptic underground tunnels anyway. Nvidia needs something better to match the speed of the AMD flagship, for example a dual-GF104 solution with both GPUs working in their maximum possible configuration.

S.T.A.L.K.E.R.: Call of Pripyat

We use the game’s DirectX 10.1 and DirectX 11 modes for graphics cards that support them.

At the two lower resolutions the tandem we are discussing cannot overtake the GeForce GTX 470 SLI, matching the latter’s performance, but then it falls behind suddenly at 2560x1600. The bottom speed is below 20 frames per second in that mode and the game is hardly playable. We don’t think this is due to its texture-mapping subsystem which is just as good as that of the GeForce GTX 470 SLI and even better since the GeForce GTX 460 SLI has a higher GPU frequency. And if the problem is in low performance of the computing subunits, the situation can only be improved by unlocking all the 384 ALUs of the GF104 chips. The Radeon HD 5970 doesn’t feel a lack of computing resources and performs very confidently at 2560x1600, making the game playable at that resolution.

Performance in Third-Person 3D Shooters

Just Cause 2

This game’s integrated benchmark does not report the bottom frame rate.

The GeForce GTX 460 SLI tandem behaves oddly at 1920x1080, falling behind the single GeForce GTX 480. It produces a good average frame rate at 2560x1600 but its bottom speed is too low. The Radeon HD 5970 is actually the only solution here to deliver a playable frame rate.

Resident Evil 5

The Resident Evil 5 results aren’t convincing, either. The GeForce GTX 460 SLI is ahead of the GeForce GTX 470 SLI at two out of the three resolutions but could only match the Radeon HD 5970 at 2560x1600. At the two lower resolutions the dual-GF104 solution was only competitive to the single-processor Radeon HD 5870.

Performance in RPGs

Mass Effect 2

We enforced full-screen antialiasing using the method described in our special Mass Effect 2 review.

Fans of this game will like the results of the test: the pair of GeForce GTX 460s is only matched by the more expensive pair of GeForce GTX 470s. That’s an achievement considering that the tested solution makes the game playable even at 2560x1600.

Performance in Simulators

Colin McRae: Dirt 2

We enable the DirectX 11 mode for graphics cards that support it.

The GeForce GTX 460 SLI performs superbly, being only inferior to the more advanced tandem based on two GeForce GTX 470s. Its performance equals that of the Radeon HD 5970 at 2560x1600, but the latter costs more.

Tom Clancy’s H.A.W.X.

The game’s integrated benchmark cannot report the bottom frame rate. We use DirectX 10 and 10.1 modes here.

This is Nvidia’s home turf where its solutions have been winning in every price category. On the other hand, you shouldn’t bother to replace your Radeon HD 5870 or HD 5970 with a couple of GeForce GTX 460 1GB cards to play this game because even top-end single-GPU graphics cards ensure smooth gameplay in H.A.W.X. at 2560x1600.

Performance in Strategies

BattleForge

We use DirectX 11 mode for graphics cards that support it.

Alas, the GeForce GTX 460 SLI cannot do much in BattleForge. It can only match the Radeon HD 5970 at 1600x900, having an advantage in bottom speed. This tandem fails at the other resolutions, its frame rate bottoming out below playable limits. There is no playing comfort at all when the game gets as slow as 5 to 12 frames per second. The GeForce GTX 470 SLI has the same problem, perhaps in a smaller degree, while the single GeForce GTX 480 feels at ease even at 2560x1600, showcasing the key advantage of the classic single-processor design, which is its independence from software optimizations today’s multi-GPU solutions can’t live without.

StarCraft II: Wings of Liberty

As we noted in our special StarCraft II report, this game cannot boast an ultramodern engine packed with advanced special effects. It is no Crysis Warhead. As a result, the game’s system requirements are modest enough. On the other hand, StarCraft II slows down considerably when you turn on full-screen antialiasing and single-processor RV870- and GF100-based products may prove to be too slow then. That’s where dual-processor solutions like the Radeon HD 5970 or the hypothetical GeForce GTX 490 come in. They deliver similar performance, AMD’s product being somewhat faster at lower resolutions.

World in Conflict: Soviet Assault

Nvidia’s dual-processor solutions seem to reach their ceiling here: the SLI subsystems based on GeForce GTX 470 and GeForce GTX 460 1GB cards offer the same speed at 1600x900 and 1920x1080. The GeForce GTX 460 SLI is as fast as the Radeon HD 5970 at 2560x1600. That’s a splendid performance because that pair cards is going to cost about $460 whereas the AMD flagship is more expensive.

Performance in Synthetic and Semi-Synthetic Benchmarks

Futuremark 3DMark Vantage

We minimize the CPU’s influence by using the Extreme profile (1920x1200, 4x FSAA and anisotropic filtering). We also publish the results of the individual tests across all resolutions.

The GeForce GTX 460 SLI is not a failure, yet cannot score more than 13,000 points whereas the Radeon HD 5970 can do that.

The SLI tandem we are interested in is ahead in both tests at 1600x900 but falls behind the Radeon HD 5970 at the higher resolutions.

Final Fantasy XIV Official Benchmark

This benchmark produces an incomprehensible result in points, so we use Fraps to get more understandable numbers. It can only run at 1280x720 and 1920x1080.

As we wrote in our previous reviews, FF XIV prefers the Radeon HD 5000 architecture. Therefore, we are not surprised at the results of the GeForce GTX 460 SLI tandem. Moreover, it is inferior to the single GeForce GTX 480 at 1920x1080 although has a high enough frame rate.

Unigine Heaven benchmark

The GeForce GTX 460 SLI is far from brilliant in this test. This test favors Nvidia, but the tested SLI tandem cannot overtake the Radeon HD 5970. Even though that’s a good result considering the pricing of these solutions, we expected more from the pair of GeForce GTX 460 1GB cards here.

Conclusion

As we wrote in the Introduction, the GF104 would be a perfect choice for Nvidia’s new top-end dual-processor graphics card because the previous new-generation processor GF100 consumed too much power and dissipated too much heat for that. The GF100 also has a wide memory bus which would make the wiring of a dual-GF100 card too sophisticated. The GF104 is free from such drawbacks. But as Nvidia has not yet released such a dual-processor product, we benchmarked what we thought would be the closest analogue, i.e. a pair of GeForce GTX 460 1GB cards working in SLI mode. As a matter of fact, every dual-GPU GeForce represents a SLI tandem. What have we found out in our tests?

Let’s take a look at the summary diagrams.

The GeForce GTX 460 1GB boasts superb scalability. The performance growth from enabling the SLI mode is 75% on average and over 100% in individual applications. The GeForce GTX 460 SLI is an average 10% ahead of the Radeon HD 5970 but the latter is faster in some tests, especially in Resident Evil 5. That’s a good start, considering that the SLI configuration is cheaper, but the resolution of 1600x900 pixels is rather too low for such monsters as Radeon HD 5970 or our hypothetical GeForce GTX 490.

At the resolution of 1920x1080 the GeForce GTX 460 SLI is not that confident. Its average advantage over the Radeon HD 5970 has shrunk to a mere 3% and it loses to the latter 10 out of the 19 tests (the biggest gap can be seen in Metro 2033, Just Cause 2, Resident Evil 5 and Final Fantasy XIV Official Benchmark). This is not a failure, yet we wouldn’t call that a victory over the AMD flagship. The GeForce GTX 460 SLI is also an average 10% slower than the GeForce GTX 470 SLI, which is nice considering the difference in their cost and power consumption.

For all its impressive potential, the GeForce GTX 460 SLI tandem cannot show a really good performance at this resolution which is the most important one for premium-class graphics subsystems. Again, the AMD flagship wins with a score of 10 to 9, but the SLI configuration is now slower by an average 5% (and much slower in individual tests like Metro 2033). The only real success of the GeForce GTX 460 SLI at 2560x1600 is its performance in Mass Effect 2 where it is much faster than the Radeon HD 5970 in terms of bottom speed.

The results of the GeForce GTX 460 1GB pair in SLI mode are somewhat disappointing overall. We had expected more from it. Although it is competitive to the mighty Radeon HD 5970 in a number of tests, Nvidia cannot claim to have the upper hand if its hypothetical dual-processor GeForce GTX 490 is based on cut-down GF104 cores with 336 stream processors. Yes, the lower price is an advantage, and purchasing a couple of GeForce GTX 460 1GB cards is going to be a good investment for gamers who want to enjoy maximum performance in their favorite games, but this SLI configuration cannot open new opportunities. Perhaps that may be possible with a dual-GF104 card in which all the ALUs are unlocked in the GPUs.

Anyway, AMD should think about cutting the price of its Radeon HD 5970 because the GeForce GTX 460 SLI looks more appealing with the current prices.

Zotac GeForce GTX 460 1GB Summary

The Zotac GeForce GTX 460 1GB we used in our tests is a copy of Nvidia’s reference card and we like it less than the original version from Palit/Gainward. The reference card has a questionable cooling design in which the improper placement of the connectors on the mounting bracket prevents the hot air from going out of the system case freely. Coupled with the modest heatsink, this leads to a high level of noise the cooler has to produce to keep the temperature low. On the other hand, this card overclocks well and is stable. You can buy it if you don’t mind its noise or if you plan to replace the reference cooler with something more effective. The Zotac GeForce GTX 460 1GB comes with a copy of Prince of Persia: The Forgotten Sands.

Highs:

 Lows: