Power Consumption, Temperature, Noise, Overclocking
As we have transitioned to a more accurate and progressive method of measuring power consumption of modern graphics cards, we will retest the Radeon HD 5700. The testbed is configured as follows:
- 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 is based on the measurement tool developed by Oleg Artamonov and described in his report PC Power Consumption: How Many Watts Do We Need?. The tool facilitates and automates the measurement process.
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.
We got the following data using the new method:
Notwithstanding its abundant resources, the graphics card is very economical in the Windows 7 desktop mode but decoding a VC-1 stream from a Blu-ray disc calls for a serious increase in power consumption. The Radeon HD 5770 should be given credit for not reaching a load of 4 amperes on the external power connector even under the demanding Crysis Warhead. The peak power draw is less than 80 watts. It is only under the synthetic OCCT: GPU load, which cannot occur in real-life applications, that the card needs more than 100 watts.
The junior model of the series behaves in the same manner. But as it has a lower GPU frequency and a few disabled subunits, its power consumption is lower: 30 watts when decoding HD video, less than 60 watts in modern games and only about 70 watts in the synthetic OCCT: GPU test.
* - estimated
The Radeon HD 5700 looks brilliant in terms of power consumption compared to Nvidia's G200b-based products as well as to AMD's previous-generation cards. Even the GeForce GTS 250, based on the outdated G98b core and hardly capable of competing with the Radeon HD 5700 series, consumes much more.
The temperature data are somewhat unexpected. The ASUS EAH5770 is 5°C hotter than the reference card under load, which may be due to the difference in the ambient temperature during the tests. And the advanced ZEROtherm cooler installed on the PowerColor PCS HD5750 1GB GDDR5 Premium Edition is not any better than the reference card’s cooler in 3D mode and even inferior to the latter in 2D mode. Perhaps the contact between the cooler's base and the GPU was poor, yet the cooling efficiency is overall high.
We measured the noise with a noise-level meter Velleman DVM1326. The reference point for our noise measurement tests is 37dBA which is the level of ambient noise in our test lab as measured at a distance of 1 meter from the testbed with a passively cooled graphics card inside. When we installed the tested graphics cards, we got the following results:
The cooling system of the PowerColor PCS HD5750 1GB GDDR5 Premium Edition is louder than the reference one, but we could only hear it at a very short distance. At a distance of 1 meter it was as quiet as the reference cooler of the GeForce GTX 275 and much quieter than the Radeon HD 4890's cooler. The ASUS EAH5770 does not irritate the ear at all with its soft hiss of airflow.
We tried to overclock both cards we used for this review.
ASUS EAH5770 overclocked
PowerColor PCS HD5750 1GB GDDR5 Premium Edition overclocked
PowerColor PCS HD5750 1GB GDDR5 Premium Edition overclocked well enough considering that the Radeon HD 5750 is based on RV830 chips which did not pass the frequency test and/or were found to have defective subunits that made them unsuitable for Radeon HD 5770. It means the Radeon HD 5750 is handicapped when it comes to overclocking, but you can still speed one up if you are lucky with your specific sample.
Now, we are going to unite these two cards into a CrossFireX tandem and pit it against a Radeon HD 5870.