There is a lot to cover, so grab a snack and strap in as we dish out all of the pertinent details. First up, let’s check out the specifications and then we’ll cover some of the Fury X’s standout innovations before digging into some testing…
AMD Fiji GPU Block Diagram
Above is a high-level block diagram of Fiji’s inner-workings. If you’re familiar with AMD’s Tonga orHawaii GPUs, which we’ve previously covered, this diagram should look familiar. The Fiji GPU itself is an evolution of Tonga and Hawaii, but has been beefed up considerably in a number of areas. Fiji features an updated scheduler, video engine, and the new 16-bit integer and floating point instructions, along with delta color compression technologies introduced with Tonga. Other areas of the GPU, however, are built out to be roughly 50% more capable than Hawaii. For example, Fiji features 4096 stream processors, versus 2816 in Hawaii. The memory bus width on Fiji grows to 4096-bits wide thanks to HBM, versus 512-bits on Hawaii, though cards are only packing 4GB of memory. Fiji also gets a boost in texturing capabilities thanks to its 256 texture units—Hawaii has 176. Hawaii and Fiji both have 64 ROPs, however, so it’s not an across the board upgrade for Fiji.
At its reference clocks of 1050MHz (GPU) and 500MHz (HBM), Fiji and the Radeon R9 Fury X offer peak compute performance of 8.6 TFLOPs, up to 268.8 GT/s of texture fill-rate, 67.2 GP/s of pixel fill-rate, and a whopping 512GB/s of memory bandwidth. The compute performance, memory bandwidth, and textured fill-rate are huge upgrades over Hawaii and even outpace NVIDIA’s GM200, which powers the Titan X and 980 Ti, although pixel fillrate is right in-line with Hawaii and Radeon R9 290X.
AMD Radeon R9 Fury X Breakout
AMD was able to pack everything onto a PCB that’s not much bigger than mainstream GPUs at about 7.5”. It does, however, have a TDP that clearly falls into enthusiast territory at 275W. As such, the card requires dual 8-pin supplemental PCI Express power feeds.
To keep the entire assembly cool, AMD strapped a close-loop liquid cooler onto the Fury X that’s capable of dissipating 500W. That may sound extreme, but there’s a reason AMD went that route on this card, and it’s not because they had to. There will be air-cooled Fury and Fury Nano cards coming in a few weeks that feature fully-functional Fiji GPUs, though we’re not sure what the clocks are going to be just yet. What the high-powered liquid-cooler on the Fury X does is allow the use of an ultra-quiet fan, with the side benefit of keeping the GPU very cool (relative to most other GPUs) under both idle and load conditions. And keeping the GPU cool (think around 60’C max under load and 30’C at idle) helps reduce overall power consumption by limiting leakage current, which wastes power. Leakage increases as temperatures go up.