Power Consumption, Temperature, Noise and Overclocking
It is the first time that we ever test a GF106-based product, so we are interested in learning about its power consumption. We performed our measurements using a special testbed with the following configuration:
- Intel Core 2 Quad Q6600 CPU (3GHz, 1333 MHz FSB x 9, LGA775)
- DFI LANParty UT ICFX3200-T2R/G mainboard (ATI CrossFire Xpress 3200 chipset)
- PC2-1066 SDRAM (2x2 GB, 1066MHz)
- Enermax Liberty ELT620AWT PSU (620W)
- Microsoft Windows 7 Ultimate 7 64-bit
- CyberLink PowerDVD 9 Ultra/"Serenity" BD (1080p VC-1, 20 Mbit)
- Crysis Warhead
- OCCT Perestroika 3.1.0
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:
- CyberLink PowerDVD 9: FullScreen, hardware acceleration enabled
- Crysis Warhead: 1600x1200, FSAA 4x, DirectX 10/Enthusiast, "frost" map
- OCCT Perestroika GPU: 1600x1200, FullScreen, Shader Complexity 8
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. The tests were performed twice: at official Nvidia frequencies and at default frequencies for Zotac GeForce GTS 450 AMP! card. Here are the obtained results:
The GeForce GTS 450 finds it hard to match the energy efficiency of the Radeon HD series even when working at the reference frequencies recommended by Nvidia. It is only in low-load modes when the new card consumes less than the Radeon HD 5700 products thanks to lowering its GPU frequencies. But when it comes to 3D games, the red team wins because the RV840 chip is simpler than the GF106 and does not clock its shader domain at a double frequency like the GF106 does. Yes, the Fermi architecture is superior to the ATI Evergreen in some respects but this superiority has its downside like the lower energy efficiency and higher heat dissipation.
Oddly enough, the factory overclocking of the Zotac card does not increase its power consumption much. The peak power draw is only 95 watts in 3D mode. Note also that the Zotac GeForce GTS 450 AMP! doesn’t use the +3.3V line at all. When overclocked, it increases its power consumption through the external power connector whereas the load on the power section of the PCI Express slot doesn’t change much. Overall, the Nvidia GeForce GTS 450 consumes about as much power as is expected from a graphics card of its class and complexity. However, it cannot match the energy efficiency of the ATI Radeon HD 5700 series in graphics-heavy applications.
The GF106 chip doesn’t produce too much heat. Coupled with the large 80mm fan in the cooling system, the Zotac GeForce GTS 450 AMP! keeps its GPU as cool as 70°C and lower even when running 3D applications. Considering its rather small heatsink, this is an excellent performance of the cooler. The only thing you should take into account is that there should be no other card in the neighboring slot that might block the Zotac card’s fan. This is true for any other graphics card with similar cooler design, though.
The Zotac GeForce GTS 450 AMP! is also good in terms of noisiness. The card is almost silent under load. We could not hear it amidst the noise from the rest of the components in our testbed. Our digital noise level meter reports that the noise is only 1.8 dB higher than the ambient noise of 38 dBA. Perhaps the Zotac GeForce GTS 450 AMP! can be heard in absolute silence, but you need a silent computer for that. So, we don’t think that anyone will find fault with the noisiness of this graphics card.
Now we are going to put our GeForce GTS 450 to some real-life tests.