AMD Radeon HD 7970 Roundup: Contenders from ASUS, Sapphire and XFX
We felt that it was pointless to run benchmarks on the cards since they are all based on the reference PCB design and no new drivers (Catalyst 11.12 with Tahiti XT support) have since been released by AMD.
Having said that, the XFX is actually clocked at 1000/1425MHz, which is still conservative but higher by 8% than the ASUS/Sapphire offerings. Thus if overclocking is not in the equation then XFX has the fastest card here.
For some reason like if you have been living under a rock, here are the links to our reviews:
A reminder of how good the HD7970 is:
On all our cards without modifications or voltage increase, we managed to push 1125MHz on the core which is the maximum that stock bios allows CCC Overdrive to be set to. For memory we had varied results from 1500MHz to 1575Mhz, which doesn't really tell us anything as RAM max frequency is usually dependent on luck even from the same batch.
On the ASUS card, we could go higher with the help of GPU Tweak which allows for voltage controls and higher clocks to be set. Heres what we managed:
Regular readers will have spotted these images before – it is exactly the same as those in our software voltage modification feature piece that we published on New Year's Day. Kudos to ASUS for bothering to bundle this with their boards to help board owners maximize the potential of the 28nm GCN architecture.
Temperature / Acoustics
In this section, we will attempt to find the thermal abilities of the reference cooler (ASUS and Sapphire) vs XFX's dual fan cooler by using OCCT GPU Burn In test (shader complexity 8) which induces full loading.
For temperature testing, we set the fans to 100% manual speed and power control to +20% to mitigate the effects of any throttling
Reference Cooler result: Max 63 degree celcius
XFX cooler result: Max 74 degree celcius
Factually speaking, the XFX cooler has lost out here in absolute maximum cooling potential by about 10 degrees with the same load applied. However we must point out that the blower fan on the reference design makes a huge ruckus at 100% (6000RPM, imagine the sound of a grassblower) while the XFX was making a tolerable whoosh sound which should be drowned out when put in a case. On normal (BF3) gaming loads and using the default auto fan profiles, both types of coolers were reasonably silent, with the XFX edging out due to a more gentle fan ramping slope on its bios.