Heavyweights: Noise and Power Consumption

Noisiness is an important characteristic of a modern graphics card. No one wants a graphics card that roars like a taking-off plane even if it beats every other card in sheer speed. This is especially important for super-fast multi-GPU subsystems, so we measured the amount of noise they produce.

The results are discouraging. The ambient noise level equaling 43dBA, the Nvidia GeForce GTX 285 3-way SLI configuration is as loud as 60dBA in 3D applications. This is far from comfortable. The Radeon HD 4870 X2 4-way CrossFireX is not much better. Although it has two rather than three fans, the cooling system of the Radeon HD 4870 X2 has been criticized for producing too much noise. The 3-way configuration based on Radeon HD 4890 is the quietest of all, yet not quite comfortable, either.

These results come as no surprise because graphics cards in top-speed multi-GPU subsystems reside close to each other and work in very cramped conditions where they can get but little fresh air for cooling. This is especially true for the GeForce GTX 285 3-way SLI. The system having no air for breathing, the GPUs and other components quickly get hot and the cards have to step up the speed of their fans to avoid overheat. And even this may sometimes be useless. Our testbed would occasionally overheat and hang up during our tests and we had to wait for it to cool down to go on with the benchmarks.

This proves that the development of gaming 3D graphics hardware has almost reached a dead-end. Even installing as many as three top-class expensive graphics cards into your computer cannot ensure an acceptable speed in games like Crysis but brings about stability and compatibility issues and a huge increase in noise, power consumption and heat dissipation. Anyway, if you dare assemble one of the abovementioned systems, you must make sure beforehand that your system case can accommodate three dual-slot graphics cards and has good ventilation. Otherwise, you’ll have a lot of problems.

Our power consumption testbed cannot measure the electric parameters of more than one graphics card. Therefore, the numbers below are estimates calculated by summing up the power consumption of the individual cards in 3D mode.

The real numbers are going to be somewhat different because the power consumption of the Slave card is not zero even in 2D mode, but you can get a general notion of how “economical” top-performance multi-GPU solutions are.

The numbers agree with our opinion that multi-GPU technologies are a dead-end in the evolution of gaming graphics hardware. The Radeon HD 4890 3-way CrossFireX needs as much as 350 watts under load whereas the Radeon HD 4870 X2 tandem needs more than 500 watts. And they do not even guarantee a comfortable frame rate if the game developer has focused on modern visual effects but forgotten about code optimization. One thing is clear, though. If you are still bent on building a multi-GPU graphics subsystem, you should get a high-quality power supply with wattage rating of 750W and higher.