Overclocking, Power, Temperatures, Fan Noise
Power consumption is not really as important on high-end consumer graphics cards as more users are comfortable with using up lots of juice to get their gaming experience where they want it to be. Still, looking at the relative power consumption of the GPUs presents interesting information on how the parts compare in terms of compute efficiency.
Overclocking the HD 7970 actually gives us a 10% boost in the required power of the GPU, not too bad but it is indicative of the problems that might arise as we increase the clock speed further.
In our quick CrossFire power test we see that adding in the second card increases power consumption by about 230 watts – pretty much spot on with the expected TDP of the GPU
Let’s see how the temperatures on the XFX Radeon HD 7970 compares to the reference design.
While XFX is touting the cooler on the Black Edition as being more efficient than the reference cooler, in our testing in Battlefield 3 that isn’t the case. The XFX card uses about 10 watts more power under a full load.
Sound levels on the XFX Radeon HD 7970 3GB are pretty close to the levels of the reference card but are definitely not any better.
We decided to push the XFX card up as high as it could go and to our delight and our frustration, we hit the 1125 MHz wall set by the Overdrive portion of the AMD Catalyst Control Center.
Performance scaled very well with this 12% increase in the clock speed as our 3DMark11 results moved from 8055 to 8879 on the GPU score, an increase of 10%.
Hopefully we will see some software available soon that will let us push these cards beyond the 1125 MHz limit we reached here.