Let’s Clear the Air: Decoding Technical Jargon
With Sony revealing the PlayStation Slim and Playstation Pro yesterday, along with Microsoft’s reveal of the Xbox One S at E3, there have been a lot of terms use that the average consumer may not be familiar with. Terms like “teraFLOPS of compute performance” and HDR make consoles and video cards sound impressive but what do they actually mean?
Let’s start with FLOPS, or Floating-point Operations per Second. Computers can basically do two kinds of math: with decimal places (floating-points) and without decimal places (integers). Floating-point math is critical for scientific computation, including simulating 3D objects and environments, which is basically what a game is. Processor speed is measured in Hertz (Hz), or cycles per second. If a processor is able to execute 100-million instructions per second its speed is rated at 100,000,000 Hz or 100 megahertz (MHz). Modern processors are typically in the range of 3 gigahertz (GHz), or 3-billion instructions per second. Depending on the processor it might be able to perform a single floating-point operation per clock cycle, or maybe it can do 4, 6, or 8 (which also depends on how much precision (how many decimal points) are used in the math). This is one of the reasons that CPUs rated at the same speed can produce different results. So if our 3 GHz processor can perform 8 FLOPS per cycle, that’s 3-billion times 8, or 24-billion FLOPS (24 gigaFLOPS). Of course, modern processors might have 4, 6, or 8 cores, so if we assume we’re looking at a 4-core CPU we need to multiply that number by 4, so we now have 96 gigaFLOPS.
CPUs have to perform a wide variety of computational tasks. Being a jack-of-all-trades means they aren’t quite as fast as a processor that’s dedicated specifically to floating-point calculations. This is where video cards (GPUs) come in. GPUs are purpose-built for doing as much floating-point math as possible. That means that, while a typical desktop CPU might perform somewhere in the 50-100 gigaFLOP range, mid-range GPUs can perform in the 3-5,000 gigaFLOP (3-5 teraFLOP) range.
Now that we know what a FLOP is and how it’s calculated we can look at what Sony claims the Playstation 4 is capable of. This chart from AnandTech shows the GPU performance between the original and Slim Playstation 4 models at 1.84 teraFLOPS (1,840 gigaFLOPS) and the Playstation 4 Pro at 4.2 teraFLOPS (4,200 gigaFLOPS). That 2.3x performance jump means that games can run at higher resolutions, texture and model detail, higher and smoother frame rates, or any combination thereof. Is it enough for native 4K? Probably not. Comparing that 4.2 teraFLOP number to a desktop GPU, it’s right in between a GTX 970 and 980, meaning it’s closer to a 1440p or 2K resolution performer unless you really dial down the rest of the graphics settings.
“But the PS4 Pro supports 4K. How is that possible if it isn’t powerful enough for 4K games?” It might not be able to render typical games in 4K resolution, but it might be possible to render it at 2K resolution and upscale the images to 4K. It’s basically like resizing an image in Photoshop, but with a little bit of sharpening and other effects to make it look kind’a like it maybe was originally rendered in 4K. Similarly, if you have a 1080p display, the system could still render a game at 2K and down-sample that image to 1080p, resulting in sharper, more natural images. This technology is already available on the desktop with nVidia’s Dynamic Super Resolution. The PS4 Pro is, however, capable of playing 4K video through services like Netflix and YouTube, though it looks like the Pro does not include Ultra-HD Blu-Ray support, so you won’t be able to watch your 4K movies on your new Playstation.
One of the other new features that was announced is HDR, or High Dynamic Range. Imagine you’re indoors on a bright, sunny day. You’re taking a picture of your friend, who is standing in front of an open window. One of two things is likely to happen: First, your camera may correctly determine your friend needs to be exposed correctly, leaving the background “blown out”, virtually pure white, or it may try to expose for the outdoors, leaving your friend as a blacked out silhouette. This is an example of a low dynamic range. When you look at your friend with your eyes, though, you can see your friend clearly as well as what’s outside with no trouble at all. This is an example of high dynamic range. HDR video aims to provide a more lifelike range of color and brightness than a typical TV or computer monitor is capable of.
That’s all I can think of for now. If you have any questions about fancy-pants words companies are throwing around in their press announcements leave a comment below.