Having seen that the GTX680 and the HD7970 are matching each other blow for blow, we of course have to see how the scaling performs in multi-card scenarios.
As one would expect at release time cards are thin on the ground and so although we can't bring you our full Overkill3D style Quad results, we have been able to get a couple of cards together to see how the new Kepler handles itself in SLI.
For this we of course have to thank our good friends at Zotac who always come through when we need them. Because the current wave of cards are still all reference models we've paired it up with our earlier reference card. So it's a bit mix and match, but beneath the stickers they're all identical anyway.
So enough preamble and on with the testing.
Being a reference model the only differences are in the bundle that you get along with the card and Zotac shine once again with an excellent set of adaptors and games for your new card. It's nice to see something other than Dirt 3 being included to be honest.
|Interface||PCI Express 3.0* x16 (Compatible with 1.1)|
|GPU||GeForce® GTX 680|
|Core clock||1006 MHz (base) - 1058 MHz (boost)|
|Shader Clock||2012 MHz|
|Memory Clock||6008 MHz|
|Memory Size||2 GB|
|DVI||2 (DVI-I & DVI-D)|
|VGA||(With included DVI-to-VGA adapter)|
|Max Resolution||2560 x 1600|
|SLI Supported||Yes (3-way)|
|Cooler||With fan (dual-slot)|
|Dual-Link DVI Supported||Yes|
|Windows® 7 Capability||Certified for Windows® 7 with DirectCompute support|
|Package Contents||Driver Disk|
2 x Dual MOLEX to 6-pin PCIe power cable
TrackMania 2 Canyon 3-Day Game Pass
|Game Bundle||ZOTAC Assassin’s Creed® 3-Game Pack|
A graphics card without a fantasy figure on the front. Saints be praised. The Zotac black and yellow colour scheme always looks classy and here it's nice and minimalist. After all, with such a beast inside the box, why waste excitement on the outside?
The card itself is well protected in the dense foam and heavy cardboard combination.
As well as the adaptors for power and display we have the Zotac bundle of games and drivers. If you haven't tried Trackmania it's worth a punt and you get three days with the Zotac card.
Here it is in all its glory. We get so used to cards with red trim on them that we really like the yellow Zotac scheme. Not only does it make a nice change but we think it looks better.
Otherwise the card is the same as we saw on the stock model, with nVidia green branding on the side and a dark PCB.
Outputs remain the same two, there is an HDMI, two DVIs and the DisplayPort.
Intel Core i7-3960X @ 4.6GHz
ASUS Rampage IV Extreme
Noctua NF-F12 Fans
Windows 7 Ultimate x64
Despite the two cards being so close together it's a testament to the quality of the current nVidia power management and cooling solution that our maximum temperature remains a pretty cool 77°C.
Of course the big comparison here is against the stock clocked HD7970 Crossfire result so that's what our review will focus upon.
3D Mark Vantage
Vantage has always loved the nVidia cards and even in it's patched state where the PhysX is dumped to the CPU to balance the two big manufacturers out, the SLI setup is still a fair way ahead of the AMD option, especially as the detail level is ramped up in the Extreme test.
3D Mark 11
3D Mark 11 switches around with the Zotac GTX680 SLI being miles ahead in Performance mode, and a fair way behind (600 points) as the detail level increases.
In the H.R Giger designed Alien vs Predator we see that the scaling remains as consistent as the single card results were, as only a single frame separates the two big hitters.
Batman Arkham City
The most recent Batman game seems to have taken up the gauntlet left by the original Crysis as the game most likely to give inconsistent results. A single HD7970 matches a MARS 2 SLI setup which matches the GTX680 SLI rig. It's all rather odd. What is good though is the minimum frame-rate. Now that's a 'smooth as butter' playing experience.
Continuing the theme of 'irritating games' we have Battlefield 3, which I couldn't get to work on our Crossfire tests, and so the only real comparison is against the MARS 2 for a multi-GPU setup. Still the results are excellent, it just doesn't scale quite as linearly as we'd hoped. Console ports eh.
The final of our troublesome triumvirate is Crysis 2, a game which "three installs and that's your lot" protection became a positive annoyance for a long time. EA need to learn about customer support. So with that said there aren't any of the big hitting Tahiti XT Radeons to look at, but as we're only gaining 20 FPS over the single GTX680 we're not missing much. It's worth looking at the maximum frame-rates too, as there appears to be a hard-cap of 100FPS. By that marker the 97FPS average of the GTX680 SLI is clearly pushing the game as hard as it can be pushed.
Whoa. Now here is a game that the Zotac positively hoovers up and spits out. 198 FPS average and a mile ahead of anything else we've ever tested. Ken Block might suck at rallying, but he can put his name to a high performing game.
Far Cry 2
The Dunia engine behind Far Cry 2 generally prefers the Catalyst method of rendering to the nVidia cards. However, such is the performance of the GTX680 SLI that it just edges ahead of the HD7970 CF. We also see around 95% scaling which shows that although the game might not be the freshest, the underlying engine was coded magnificently.
Although the scaling performance in Mafia 2 isn't exactly stunning, a mere 50% improvement, the Zotac clearly gives us the highest performance we've yet seen. In Mafia 2 at least, it's the Kingpin.
When we compared the single card performance it was clear that the HD7970 had a big margin over the GTX680, and when we double the cards up that becomes even more pronounced. The GTX680 SLI is dead and buried here.
Resident Evil 5 - DX9
Considering that even the lowly stock GTX560Ti can give us way over 100 FPS in Resident Evil 5, there is obviously a case of diminishing returns. The two flagship options are inseparable, but nobody genuinely believes that two GTX680s are only twice as good as a single HD7770.
Resident Evil 5 - DX10
The renderer might change to DirectX 10 path, but the result remains the same. Barely any scaling improvement and at these high frame-rates the extra card provides more of a drain upon resources than an improvement in performance.
nVidia originated the option of tessellation on our GPUs and Unigine Heaven makes good use of this. The Zotac GTX680 SLI setup spanks the Radeon option pretty handily and the scaling is magnificent.
Ramping up the image quality settings lessens the gap considerably with the SLI setup being just a shade ahead of the Crossfire arrangement. Once again we're seeing outstanding scaling performance.
The Witcher 2
Finally, as always, The Witcher 2. When it was first released there was a heavy warning that Ubersampling was designed for an as-yet-unmade future GPU. Whatever it was designed for, the Zotac GTX680 SLI is it, giving us 100% scaling performance and a whopping 70 FPS average. Incredible. If you really want to know what games will look like in the future, you owe it to yourself to play this game on this setup.
So what have we learnt today? Quite a bit we reckon.
First up is the insane amounts of performance available from the very top-end cards. Both the HD7970 and the GTX680 are CPU limited in the majority of scenarios, even with a 4.6GHz i7-3960X powering them. So powerful are they that a lot of titles just cannot stress them enough to make the extra card worthwhile.
Even more than that, if you really want to make the best out of your new setup, then you need to be very selective in your choice of game. Generally speaking, and we're not playing the 'PC Gamer Master Race' card but it's true, if you want to test your cards to the fullest of their potential then you need to choose a game which is designed as a PC game from the ground up, rather than one that's been retro-fitted from Console roots. Crysis 2 took a couple of patches to get the level of detail we demand, and even then it's clear it has a 100FPS cap on it, despite having vsync off. Equally Battlefield 3 and Batman Arkham City are as reliable as a British Leyland car. But step away from those titles to the ones that have PC roots, Far Cry 2, Mafia 2, The Witcher 2, and you find a bevy of games capable of either stressing your system to the ultimate, or at least giving you exceptional performance boosts for your second card.
As for the Zotac itself, it's still at its heart a reference card and so the main reason you'd choose it over any other would be the bundle that you get with it and or the after-sales support. The bundle is excellent with a lot of great titles, a taster of another, and the usual high quality Zotac manual. The after-sales support is, and we speak from personal experience, fantastic. If the worst does happen they have a no-fuss, quick turnaround to get you up and running as fast as you could realistically hope. Plus you get a card that stands out a bit thanks to the use of yellow rather than the ubiquitous fire-engine red.
Now we already know that the GTX680 is gold-worthy, and the quality of the Zotac name and bundle mean that this is just as true with today's card and it will be awarded our highest honour. Stepping away from that for a moment and going back to the SLI scaling, we have to say that we're eagerly awaiting some updated drivers from nVidia. Anyone who has a multi-GPU setup knows that every few months nVidia release an update that boosts SLI performance by a huge amount. So right now it's neck and neck between a GTX680 SLI and HD7970 Crossfire and no matter which you choose you'll be happy. Past experience tells us that in six months the situation could lean heavily towards the nVidia models. Of course we don't take potential in to account in our reviews, but it's worth noting.
So if you've got money to burn and desire only a handful of games, then SLI has all you could require.
If you're just wondering which of the many reference-design brands of GTX680 to choose, the bundle and customer service from Zotac should put this firmly to the top of your list, which is why it unquestionably gets our OC3D Gold Award.
(scores are solely based upon a single Zotac GTX680)
Thanks to Zotac for supplying the GTX680 for review. Discuss in our forums.