Nvidia’s GTX 680 arrives! “Faster, Smoother, Richer” – is it enough to take the Performance Crown?

Overclocking, Power Draw & Temperatures

Overclocking

Overclocking the GTX 680 beyond the stock overclock was easy.  No one should let the boost clocks intimidate them.  Using EVGA Precision tool, simply push the sliders to the right as far as you dare and set the clocks.  No more shader clocks to adjust and the vRAM and the core are easy to set.  As usual, we are not looking for the ultimate overvolted overclock with our VGA fan screaming along at 100%.  We always test with our cards at stock voltage and with the stock fan profile so that our reader may have a good idea of midrange overclocking.

As you can see, we upped the base clock by +150MHz over the base clock of 1006GHz for 1156MHz and GPU Boost adjusts the frequency upward by another +100MHz to top out at about 1260MHz.  We also set the power target to the maximum 132% and upped the memory clock by 25MHz (eventually).  Fan speed stayed low and temperatures in the mid-50s under load.  Of course, at idle the voltage and the clocks dropped.

Power Boost will continually adjust the clocks and the voltage dynamically per each application.  Below we see 1005MHz and have seen it fluctuate upward to 1285MHz with the same application,

We did exactly the same thing with our PowerColor HD 7970.  Its stock clocks are 925/1375 and we pushed them beyond the fastest AMD partner-overclocked Radeon HD 7970’s clocks at 1070/1400MHz to exactly 1100MHz/1400MHz at stock voltage and with the stock fan profile.  And our particular HD 7970 was not completely stable at anything over 1100MHz on the core without upping the voltage.

With our GTX 680, we reached 1156MHz on the core and upped the memory +25Hz to 3025MHz.  That 1156Mhz is +150MHz over Nvidia’s stock core clock and that does not count further overclocking of approximately +100MHz provided automatically by GPU Boost.  On the other hand, the +25MHz total memory boost is quite conservative.  We could have gone much higher on the core and on the memory if we were willing to turn up the fan speeds or adjust the voltage but we are saving that for the follow up article.  As it was, core temps are not the sole limiting factor on our overclock of either the HD 7970 nor the GTX 680 as far as we can see.

We always use EVGA’s Precision overclocking tool which recently added integrated GPU voltage adjustments.  In addition to the EVGA GeForce GTX 680, EVGA has also introduced a new version of its popular “Precision” overclocking software, EVGA Precision X. It allows you to fine tune your GeForce graphics card, including GPU Clock speed, GPU Voltage, Memory Clock speed and Fan speed.

EVGA Precision X features many new and key features:

• · Brand New GUI – Built from the ground up for the next generation of graphics accelerators.
• · Advanced Hardware Monitoring – See GPU vitals in real time.
• · In Game Monitoring – See your GPU vitals, without leaving your game.
• · Frame Rate Target – GeForce GTX 680 will adjust power/clock dynamically to match set framerate.
• · Fan Curve – Setup and advanced fan profile.

Learn More about EVGA Precision X

Temperature

Our ambient (room temperatures) were fairly warm – 72-76F – so as to approximate a warm Spring day. Be aware that we used our Thermaltake Element G case which has excellent airflow for an oversized midtower.  The GTX 580 Ti runs quite cool at even our overclock, in the low to mid-50s C even under load.  However, once the core speed increased, so did the temperatures until we were idling in the low 60s when we hit near the 1300MHz peak on the core from boost and temperatures would rise into the low-80sC.

You can see from the performance charts what effects increasing core speed has on the GTX 680  – from the reference speed of 1006/3006MHz , to our own +150MHz.  The performance summary charts are up next and there is a separate overclocking chart showing the manual overclocking of the GTX 680 +150MHz on the core compared to the +175MHz we got with our PowerColor HD 7970.

We are looking forward to our follow-up article which will include voltage increases for both the GTX 680 and the HD 7970.  So far, they both seem to overclock equally very well.

Power Draw

We did a rough comparison by using our entire system running identical stressful benchmarks while monitoring with Kill-A-Watt.  Here is the GTX 680 in our system at idle.

Now we ran our benches continually and looked for the peak usage of power with our GTX 680 overclocked as far as it would go stably without  fan profile adjustment nor with a voltage increase.  The absolute peak power usage was a blip at 451W.  We couldn’t quite catch it, but we got close.

Installing the overclocked HD 7970 into the same system drew 44W more than with the overclocked GTX 680; we photographed the peak Wattage that we observed.   The PowerColor HD 7970 was also overclocked as far as it would stably go – also on the stock fan profile and stock voltage.

Noise

Both cards are extraordinarily quiet for high-end flagship cards.  The GTX 580 is already quiet for a powerful card, but both of these cards are noticeably quieter.  And we had to drop our overclock on our CPU and lower our CPU fans rpm to even notice them at all.  Both automatic fan profiles work well and needed no tweaking using our maximum overclock on each card.

It appears that Nvidia has especially tuned the GTX 680 to be quiet somewhat at the expense of cooling.  It will be interesting to see what cooling designs their partners implement.

Before we head to our performance charts, let’s do check out 3D Vision PhysX and Surround vs. Eyefinity testing.