The GTX 680 Arrives! – Part Two, Maximum Overclocking vs. the HD 7970

Performance summary charts & graphs

Here are the summary charts of 21 games and 3 synthetic tests. The highest settings are always chosen and it is DX11 when there is a choice; DX10 is picked above DX9, and the settings are ultra or maxed. Specific settings are listed on the Main Performance chart at the end of this page. The benches are run at 1920×1200 and 2560×1600 with separate charts devoted to dividing games by their DX pathway to keep the graphs relatively short.

All results, except for Vantage and 3DMark11, show average framerates and higher is always better. In-game settings are fully maxed out and they are identically high or ultra across all platforms. Let’s break down our master chart into several smaller charts and graphs. First up, let’s look at OpenGL and DX9 together, then DX10 and fnally DX11 games separately.

Futuremark & Heaven synthetic tests

3DMark11 is Futuremark’s latest DX11-only benchmark and here are the default benchmarks detailed results of the GTX 680 at maximum overclock.  Notice the voltage slider is pushed all the way to the maximum at right.

Unfortunately, scores are completely meaningless when they are presented in this way but they do offer supporting data to accompany our game benches. Here is the chart with Vantage and the detailed score:

We do not graph the synthetic benchmarks but they are presented in the Main Summary Charts at the end of this section.  Synthetic tests are interesting but they are not necessarily indicative of real world gaming performance. In all three cases, the GTX 680 “wins” over the HD 7970 and overclocking makes no difference to the ranking. Next up, let’s look at DX9 and OpenGL games.

DX9 and OpenGL

Wolfenstein is our only example of OpenGL and it is listed on our chart together with DX9 games without being mentioned as OGL. Unfortunately Rage is hard to benchmark so it will have to do until Doom IV is released. Left 4 Dead 2 represents the very popular if aging Source Engine and Serious Sam 3 BF3 is a very new and demanding DX9 game released late last year on the Serious 3.5 engine that provides impressive visuals and on ultra settings and high resolution, can slow the fastest video cards.

Here is our Open GL and two DX9 games at 1920×1200:

Overclocking actually catches the GTX 680 up to the HD 7970 in Left 4 Dead 2.  And now at 256ox16oo.

Wolfenstein is much faster on the HD 7970 although it is quite playable on the GTX 680. Both Left 4 Dead 2 and Serious Sam 3 BFE are faster on the HD 7970 than the GTX 680 although there is no practical difference in the gameplay experience. Let’s check out DX10 games

DX10 Games

We test five DX10 games. Here are the results at 1920×1200

And now at 2560×1600.

Out of these five DX10 games, only World-in-Conflict is marginally faster on the HD 7970 over the GTX 680; in Crysis the situation reverses and the GTX 680 is faster. However, the other 3 games are noticeably faster on the GTX 680. At 1920×1200 the performance gap is wider than at 2560×1600.

DX11 Games

Most of our testing emphasizes DX11 games and we bench 13.  Unfortunately, a chart with 13 games is much too long and we break our DX11 titles into “older” and “newer” which is mostly based on the date the games were released.  Here are our older DX11 games, first at 1920×1200.

And now at 2560×1600:

And now the “newer” DX11 games at 1920×1200

And now the same newer DX11 games at 2560×1600

From the above 13 DX11 games, the HD 7970 is faster in 3 games – BattleForge, Aliens vs. Predator and Metro 2033. In three games, they trade blows – Call of Pripyat, F1 2010 and Deus Ex: Human Revolution, depending on the resolution. Finally, the GTX 680 is faster in seven DX11 games that we tested: Lost Planet 2, H.A.W.X. 2, Crysis 2, Civilization 5, Shogun II, DiRT 3 and Batman: Arkham City.

And when we overclock, the position doesn’t change in favor of the HD 7970 and the performance gap with the GTX 680  is rarely narrowed by more than a percent or two with overclocking.  Even at 1200MHz, the HD 7970 fails to overtake an overclocked GTX 680.  It also generally appears that the GTX 680 continues to show its strength at 1920×1200 which diminishes a bit compared to the HD 7970 as the resolution goes up.

Main Overall Summary chart

AMD vs. Nvidia Memory Clocks

In our charts we are expressing the memory clocks as Nvidia and AMD expresses them.  You can multiply the AMD clocks by 2X to get the equivalent data rates if you wish; or cut the Nvidia clocks in half.  At any rate, Nvidia has clocked its card’s memory much higher than AMD’s. One can even multiply Nvidia’s by 2x and AMD’s by 4x if you want the double data rate expressed so they are both equal.

This is the master chart and it has not been made into a graph as there would be too much information to include and view.  All of the preceding charts and graphs are based on this two-part chart.

These same two charts are now presented so the GTX 680 is pitted directly against the HD 7970 at each step of their similar corresponding overclock, from stock right up to their individual maximum clocks.

No matter how you add it up, the GTX 680 is generally around five percent faster overall than the HD 7970; a little faster at stock and a tiny bit less when both cards are overclocked to their maximums. Both cards overclock superbly so neither card has much of an advantage over the other with headroom on stock clocks and with the stock fan profile.  We note, as the clockspeeds increase, the performance scales nicely with both architectures although the Radeon narrowed the gap very slightly when both cards were overclocked.

From our testing, 1200MHz/1575MHz is not enough for a super overclocked HD 7970 to catch the overclocked reference GTX 680.   The Sapphire “Toxic” will evidently not be fast enough to take back the performance crown for AMD.  They would have to significantly increase the clocks of the HD 7970 to catch the GTX 680.  And no matter how you look at it, the GTX 680 has a real advantage by the lower amount of power it uses to achieve the same or slightly better performance.

Let’s head for our conclusion.

«1. Introduction2. Test Configuration3. O/C'ing. Power Draw & Temps4. Performance Summary Charts5. Conclusion & The Verdict6. View All»