Efficiency: Nvidia Quadro K4000 Versus AMD FirePro W7000
The Quadro K4000 and AMD FirePro W7000 are both aimed at the average workstation customer and, consequently, are supposed to be top sellers. Their prices are also very similar, so it's only natural for us to compare them directly. Interestingly, Nvidia states that the Quadro K4000 has a thermal design power (TDP) of 80 W, while AMD's FirePro W7000’s is rated at 150 W. The two cards perform about the same in an application like SolidWorks. Take that fact, along with the power numbers, and you might assume AMD's card uses twice as much power to do the same work. But the FirePro is actually a higher-performance card on paper. Let's take a look at a couple of different scenarios.
Scenario 1: Similar Performance in Real-World Workload with Partial GPU Load
Going back to SolidWorks, we can compare the power consumption of Nvidia's Quadro K4000 and AMD's FirePro W7000. The Pitcairn-based card uses more power under lower and peak loads.
The next question is how each card's power consumption relates to its graphics performance.
AMD's FirePro W7000 draws about 10 percent more power than the Quadro K4000 and provides five percent more performance in tasks where the two cards fare close to the same. This really isn’t so bad, since a 5 W difference isn’t anything to write home about.
Scenario 2: Different Performance in Real-World Workload with High GPU Load
I didn’t want to use a completely artificial GPGPU stress test to apply 100 percent load. Instead, I opted for the Unigine Heaven 4.0 benchmark, which scales well and uses almost 900 MB of memory. This doesn’t torture the cards as intensively, but it is more realistic than a straight-up compute workload pushing each card as hard as possible.
Interestingly, the two resulting lines aren't quite identical, even though each GPU is faced with the same task. For a better chance at fairness, the two cards were warmed up to operating temperatures by a medium load from Maya 2013’s Toy Store benchmark scene.
We might have received an exceptional FirePro W7000 press sample, but it looks like the Pitcairn-based card scales very well. That means its TDP is rated very conservatively in AMD’s technical specifications. Not even a full-out stress test takes the card anywhere close to 150 W. It barely breaks 100 W in a benchmark that caused two Malta cards to thermally throttle in Radeon HD 7990 In CrossFire: The Red Wedding Of Graphics.
The bars below show us that, even though the FirePro W7000 is less efficient than the Quadro K4000 under medium loads, the opposite is true under a more taxing scenario. The ratio of power consumption to graphics performance is clearly in AMD’s favor, even though this benchmark generally tends to favor AMD a bit.
We thought it'd be interesting to repeat the experiment with a normal Radeon HD 7850 and 7870, since the technical specifications put AMD's FirePro W7000 somewhere in between those two cards. Our FirePro sample draws about as much power as the frugal Radeon HD 7850, but it performs significantly better. This outcome is plausible. Unfortunately, we couldn't try the same comparison using SolidWorks, since the test won't start with a desktop card installed.
The two examples we set up are frankly somewhat arbitrary. Nvidia's Quadro K4000 is twice as fast as the FirePro in some CAD applications, and OpenCL-based tests show the complete opposite. But the scenarios we picked are still very interesting for two reasons. First, they show how far good driver optimization can take a card. Second, they demonstrate what happens when a GPU is able to make actual use of all the theoretical performance it has on paper.