We measured the power consumption of computer systems with different graphics cards using a multifunctional panel Zalman ZM-MFC3 which can report how much power a computer (the monitor not included) draws from a wall socket. There were two test modes: 2D (editing documents in Microsoft Word and web surfing) and 3D (the intro scene of the Swamp level from Crysis 3 running four times in a loop at 2560x1440 with maximum visual quality settings but without MSAA). Here are the results:
The AMD Radeon R9 295X2 configuration is voracious indeed. Its peak power draw of 833 watts is only 17 watts lower than the minimum PSU wattage recommended by AMD. This is 143 watts higher than required by the configuration with one Radeon HD 7990 and 207 higher compared to the GeForce GTX 690. The difference between the Radeon R9 295X2 and Radeon R9 290X is up to 264 watts. Considering the identical GPU configurations, memory amount (per each GPU) and clock rates, this number seems to be indicative of the peak power draw of one reference Radeon R9 290X.
We can also note the rather modest power requirements of the Zotac GeForce GTX Titan Black at its default clock rates. It needs no more than the Radeon R9 290X configuration. Considering the Titan’s higher performance, Nvidia's top-end solutions seem to be more energy-efficient than AMD's.
Now let’s do some math. First of all, the new AMD Radeon R9 295X2 has twice more GPUs than the Radeon R9 290X and clocks them at a 1.8% higher frequency. Second, the marketing department may claim the new card has twice the graphics memory, but that’s not true. There’s 4 GB per each GPU, just like on the Radeon R9 290X, so there’s no addition or multiplication. Third, the Radeon R9 295X2 has got a rather efficient and not very noisy liquid cooling system, which is an innovation for AMD. And quite a good one. To be specific, it gives you minus 30°C at peak loads. And finally, the new dual-processor flagship is more than three times as expensive as one Radeon R9 290X. Talking about retail prices, one Radeon R9 295X2 would cost you as much as three original Radeon R9 290X cards with high-performance air coolers. If combined into a single subsystem, such a trio would be faster than an R9 295X2. Thus, the new card is not really meant for the price-conscious.
Still, we like it. Our apprehensions about the Asetek liquid cooling system didn't come true. The performance of the new card is unrivalled so far at the highest settings. The recently released Nvidia GeForce GTX Titan Z is twice as expensive and cannot be regarded as its market opponent.
So we witness the two GPU developers show their capabilities at designing super-fast graphics cards regardless of their price and market perspectives. Unfortunately, such demonstrations have little practical worth for the majority of users.