Power Consumption, Temperature, Noise, Overclockability
We measured the power consumption of our GeForce GTX 275 on a special testbed with the following configuration:
- Intel Pentium 4 560 CPU (3.6GHz, LGA775)
- DFI LANParty UT ICFX3200-T2R/G mainboard (ATI CrossFire Xpress 3200 chipset)
- PC2-5300 SDRAM (2x512MB, 667MHz)
- Western Digital Raptor WD360ADFD HDD (36GB)
- Chieftec ATX-410-212 PSU (410W)
- Microsoft Windows Vista Ultimate SP1 32-bit
- Futuremark PCMark05 Build 1.2.0
- Futuremark 3DMark06 Build 1.1.0
Following our standard procedure, the 3D load was created by the first SM3.0/HDR test from 3DMark06 running in a loop at 1600x1200 with forced 4x FSAA and 16x AF. The 2D load was emulated by the 2D Transparent Windows test from PCMark05.
The lower GPU and memory clock rates and the disabled subunits (4 RBEs and 1 memory controller section) result in a lower power draw of the new card relative to the GeForce GTX 285. The difference is not as big as to make the GTX 275 competitive to the Radeon HD 4890 in this parameter. The latter has a power consumption of 120 watts, which is 20 watts lower than that of Nvidia’s solution, and is thus the most economical graphics card in its class. The two external power connectors are loaded equally in the 3D mode.
And here is how hot the GeForce GTX 275 is:
Its GPU temperature is lower under load than that of the senior model. Such temperatures are normal for modern top-end graphics cards and should not worry you at all. By the way, the Radeon HD 4890 is ahead in this test, being 10°C cooler under load than Nvidia’s solution.
The BFG card is equipped with Nvidia’s reference cooler, yet we measured its level of noise again to see if there was any difference. There was none:
The numbers are the same as those that we had with the new version of GeForce GTX 260 Core 216. The card is quiet and, traditionally for Nvidia’s solutions with reference coolers, the only noise it produces is the hissing of the air passing through the heatsink.
Our attempt to overclock the BFG GeForce GTX 275 OC was moderately successful:
We increased the core frequencies to 720/1600MHz and the memory frequency to 1250 (2500) MHz (i.e. 50 (100) MHz higher than the rated frequency of the card’s memory chips). The frequency growth is high enough to promise a nice performance boost. Therefore we will benchmark the card at both default and overclocked frequencies. Let’s now move on to the gaming tests.