Bitcoin mining 6990 Crossfire

When we originally published our 7970 content on January 9th 2012 it wasn't possible to run Quad CrossFire with the 7970 and MSI's new X79 Big Bang XPower 2 motherboard. The configuration simply wasn't enabled. That changed overnight with a new BIOS from MSI and new driver from AMD (dated 5th January) which allowed us to test 4x7970 in CrossFire.The install process was simple, we added in all four cards and it booted fine, we then installed the driver without issue and rebooted. Each of our GPUs received the driver install and upon checking Catalyst Control Centre and GPUz we found that 4 card CrossFire had been automatically enabled.

Just to be sure we ran 3DMark with all four cards attached and the result we achieved is shown above. Exceptional results considering a single GTX 580 or Radeon 6990 score X2100 and X3500 respectively.

	Idle Power	Load Power	Idle Temp	Load Temp
Sapphire Radeon HD 7970	85w	304w	40°C	77°C
NVIDIA GeForce GTX 580	104w	324w	36°C	82°C
Sapphire Radeon HD 7970 CrossFire	497w	81/72°C
Sapphire Radeon HD 7970 Tri-CrossFire	664w
Sapphire Radeon HD 7970 Quad-CrossFire	892w
AMD Radeon HD 6990 CrossFire	749w
NVIDIA GeForce GTX 590 SLI	774w

Power use increased from 664w in 3 card mode to 892w in quad configuration and we also noted that the power down feature of the driver/hardware was working without issue on all four cards. Essentially only the first remained active at the desktop with the other three shutting down and remaining completely silent.

So the only remaining test was to run a game and see if the good 3DMark scaling could be replicated in gameplay and for this we chose Shogun 2 as it was one of the games which already scaled well into 3 GPUs...

Shogun 2 was tested at 5760x1080 with no AA, 16xAF and all other settings at their maximum.

It won't be the same for every game as the drivers are still very clearly maturing but AMD have quad scalling working well in Shogun 2. We were able to increase our average and minimum framerates by around 10fps and the maximum by even more.

Here are examples of how the game looks at our tested settings.

Summary
Quad 7970 CrossFire is clearly something for the real enthusiast and still a work in progress however for those who are willing to be patient, and have a huge budget there is nothing faster than this.