PCIe 4.0: The Next Generation of Speed is Here

19 Jul 2019

Since the advent of PCIe 3.0 in 2010, PC builders all over the world have anticipated the release of a faster component to motherboard interface, and this year they’re getting it. At Computex 2019, AMD’s CEO Dr Lisa Su announced that the new line of Ryzen 3000 processors would be PCIe 4.0 compatible, which has sent a fair number of ripples through the tech community. 

Now that we have motherboards that can support them, there are a few questions around the fourth generation of PCIe standards. Here we’re going to address two of them: what will PCIe 4.0 do for modern rigs and do we actually need them? 

Why you should care about PCIe standards 

For those who may be a little bit confused, PCIe stands for Peripheral Component Interconnect Express – a high-speed serial computer expansion bus standard. It is the interface that modern motherboards use to connect to expansion devices like graphics cards, solid-state drives and many others, by slotting into provided places on the motherboard itself. To optimise your computer’s performance, that connection between peripheral device and the PC needs to be able to handle a lot of data very quickly. This is why we have several generations of PCIe – engineers just keep trying to make it faster.

PCIe Lanes, Speeds and Bandwidth Explained 

Generation 4X Speed8X Speed16X Speed
PCIe 1.X1 GB/s2 GB/s4 GB/s
PCIe 2.X2 GB/s4 GB/s8 GB/s
PCIe 3.X3.94 GB/s7.88 GB/s15.7 GB/s
PCIe 4.X7.88 GB/s15.76 GB/s31.51 GB/s

Up until about a month ago, the world only knew of three PCIe generations. The latest, PCIe 3.0, was still managing to keep up with modern GPUs without breaking much of a sweat. After all, their high-end 16X model transferred 16GB per second each way, which is still nothing to scoff at. In fact, most graphics cards don’t even saturate the third generation, so why were the engineers behind the fourth-generation interface shooting for more? 

All of the devices on your computer need a certain amount of bandwidth to operate properly, so any interface that connects peripheral devices needs to provide enough “lanes” for the connecting devices to use. You can check the specifications of a sound or graphics card to find out how many PCIe lanes they chew up. For example, many high-end GPUs take up an entire sixteen lanes (out of a maximum of twenty-four) leaving a small amount of bandwidth for the rest of your devices to battle over.

Essentially, the more PCIe lanes you can cram into your setup the better, because they’ll leave more room for you to connect expansion kits and up your PCs performance. That brings us to PCIe 4.0, and why it could actually be a game-changer.

PCIe 4.0 and its purpose in your PC 

Sticking to their trend of doubling the processing speed of each new PCIe, the fourth-generation interface has double the processing speed of its previous incarnation. That is to say, their 16X model somehow forces 32GB of data per second both in and out of your computer. That is… insane.

But there is a critical question at play here: do we actually need processing speeds like that? As previously mentioned, most graphics cards don’t even fully employ the available power of a PCIe 3.0 standard, so from that perspective a doubled speed is just redundant. Where the new interface really shines is in terms of computer storage – your SSD.

Speed Up Your SSD

Solid State Drives (SSDs) are different to Hard Disk Drives (HDDs) in that they have a complete and total lack of moving parts. Their main advantage over HDDs is that can read and write data much faster. SSDs are a commonplace addition to the arsenal of computer parts on a gaming PC, because they ease the HDD’s burden of processing heaps of data, speeding up your computer’s performance. 

SSDs are an expansion to your baseline rig, so you can connect a PCIe SSD to your computer to get the most out of its processing power. And now that AMD has released a motherboard and processor that can handle PCIe 4.0 speeds, you can pick up an SSD that will round out what is quite possibly the fastest assembly on the market. 

Keep in mind that you have to have a Ryzen 3000 level CPU and a motherboard that boasts an X570 chipset in order to run a supercharged PCIe 4.0 SSD. But if you’ve got the dollars, then the world is your oyster.

Get the latest and greatest advice from the experts at Computer Lounge. 

We’re the ones to come to if you’re looking to build a gaming PC in New Zealand – our custom PC builder lets you build your perfect rig from the motherboard out, and you can have the result delivered to your doorstep. If you have any questions or would like to check on the availability of a component, get in touch with our friendly team


Computer Lounge