Power, Temperature and Noise
Unsurprisingly, there isn't a great deal between the two when it comes to power consumption. A near-300W, system-wide reading is in line with expectations for a high-end gaming rig.
Both coolers are working admirably, too. An under-load temperature of 73ºC is well within limits for MSI's GeForce GTX 780 Ti Gaming, and it allows the card to run without any throttling concerns. Indeed, during this particular test, we clocked the GPU running at speeds of up to 1,071MHz.
There is an audible difference between the two cards, mind you. Sapphire's Radeon is reasonably quiet for an overclocked R9 290X, yet its fans are having to work much harder than MSI's and consequently create more noise. The Twin Frozr ticks all the right boxes - it's fast, it runs cool, and it's one of the quietest GTX 780 Tis we've ever tested.