If graphics cards don’t need it, what’s the point of PCIExpress 4?

A component plugged into a PCIe slot | Does PCIe matter?

PCIe 4 is finally here. AMD’s upcoming Ryzen 3000 generation of CPUs are backwards compatible with most first and second-generation, 300 and 400 series motherboards. But the 500 series, and more specifically the X570 chipset, introduces some exciting features, including support for PCIe 4.0. But considering graphics cards of today don’t even max out PCIE 3.0, and many of AMD’s flagship X470 motherboards from 2018 actually ran PCIE 2.0, is there really much point to the new standard?

The answer is actually, yes. Despite mainstream graphics cards not needing anything close to the full (almost) 32GBps of unidirectional bandwidth that PCIe 4.0 x16 ports offer, there are some very real benefits to the new standard and they could make upgrading to the new 500 series motherboards worthwhile for AMD fans. And even Intel ones. Especially if the projected performance for Ryzen 3000 is anything to go by.

More bandwidth means more lanes

When it comes to PCIe lanes, graphics cards are the most hungry for them. The top-tier GPUs like Nvidia RTX 2080 Ti and AMD’s Radeon VII require masses of bandwidth to pump out the high frame rates and details that they’re capable of. But even these cards don’t need what PCIE 3.0 x16 slots offer. So, why is PCIE 4.0 a benefit? Because it means that gamers won’t need to run their fastest graphics cards in the fastest configuration.

A 2080 Ti pushes the limits of what a PCIe 3.0 x8 port will allow, just – TechPowerUp’s testing proves that. So, on a board with PCIe 3.0, running it in an x16 configuration makes the most sense. But that means the graphics card alone is hogging the all 16 lanes of PCIe. On an AMD Ryzen CPU, be it first, second, or third-generation, there are only 24 lanes to go around. Four of those are set aside for PCIe and SATA drives, four more provide the link with the chipset (which has a number of lanes of its own and shares them between storage drives and USB ports), and 16 dedicated for graphics cards.

Navi GPU that's PCIe 4 ready

Intel CPUs do things a little differently, but has the same 16 lanes for the GPU(s) they’re paired with. To get any more than that, you’d need to look to HEDT systems like Intel’s Core i9 X and XE CPUs, and AMD’s Threadripper chips (they aren’t dead, no matter what you hear), which have 44 and 64 lanes, respectively.

With PCIe 4.0, however, there’s no need to run a graphics card with the full 16 lanes, because x8 mode will give more than enough for even a 2080 Ti. That means unlocking an extra eight lanes (or more in the case of lower-power GPUs) that can be used for a variety of additional purposes.

What can we do with more lanes?

The obvious answer might seem like more graphics cards! But multi-GPU support in 2019 is limited at best, with both AMD and Nvidia having moved on from their respective multi-card technologies, with few game developers really taking advantage.

We could see those lanes leveraged by more niche use cases, like multi-GPU cryptocurrency mining rigs, but we don’t expect many outside of benchmarkers and heavy-overclockers to really leverage multiple graphics cards any more with PCIe 4.0 than they do now.

Gigabyte even demonstrated four 2TB M.2 SSDs on a single card with maximum read and write speeds in excess of 15GBps.

More likely and more useful, is that those lanes could be used for a variety of add-in cards. If you want the fastest storage possible, PCIe 4.0 NVME drives are at the forefront and some have already been announced with sustained read/write speeds as high as five GB/s. That’s 10 times the speed of your average SATA III SSD.

While those kinds of speeds aren’t going to deliver much in the way of a reduction in game load times or Windows boot times over today’s fastest PCIE SSDs, or even much beyond SATA SSDs, for those dealing with large amounts of data or regularly performing big file transfers, that massive storage throughput could come in handy.

With less of a reliance on chipset PCIExpress lanes, PCIe 4 enabled home RAID setups of multiple high-speed NVMe drives for even more sustained read/write headroom, are perfectly viable too. Gigabyte even demonstrated this as Computex with four 2TB M.2 SSDs on a single card with maximum read and write speeds in excess of 15GBps.

PCIe ready

It needed its own cooling fan and shroud, like a miniature GPU, but what’s another fan when it comes to extreme storage performance?

Faster networking is also a more viable option with PCIe 4.0. 10-gigabit Ethernet could be possible on just one dedicated lane, making it far more accessible for the average person. Additional USB or Thunderbolt 3 ports could also benefit from those free lanes, allowing for more accessories and peripherals.

Those Thunderbolt 3 ports could come in extra handy in the laptop space. With additional bandwidth and dedicated lanes that don’t have to rely on the chipset’s more limited connection to the CPU, we could see external graphics cards compete directly with onboard GPUs for the first time. That would make external enclosures like Razer’s Core X Chroma, a real alternative for laptop owners who want gaming power at home and a more portable, longer battery-life device during their work day.

It’s also possible that games built for new-gen consoles like could take advantage of faster storage drives on PC too.

Outside of home PC users, data centers, and supercomputers could see real benefit from PCIe 4.0 too. All of that additional bandwidth could enable larger arrays of GPUs for high-end rendering tasks and number crunching on an extreme level. Those looking to run a large number of displays on a single system too, could see a benefit.

So, is it worth upgrading for?

As is usual with the bleeding edge technologies in the PC space, PCIe 4.0 is not going to transform your home PC experience in any meaningful way right away. If you’re an everyday gamer, or even one running some of the most powerful hardware in the world, you aren’t going to see a big difference in your FPS because of PCIe 4.0 alone.

It does open up the ability to better utilize multiple graphics cards and even faster NVMe drives, but neither of those are that important for most people right now.

That will likely change in the future, though, as new generations of graphics cards pushing the bandwidth boundaries of what PCIe 3.0 can do. It’s also possible that games built for new-gen consoles like Sony’s PS5 with near-non-existent load times, could take advantage of faster storage drives on PC too. At that point it will be within the interest of gamers wanting to make the most of their hardware to upgrade. But we’re not there yet. Not even close, really.

PCIe 4.0 is a neat addition to the Ryzen 3000 platform that AMD will launch in July 2019 and is something it can hold over Intel as a feature that is exclusive to AMD systems for now. Those who can take advantage of those additional lanes and bandwidth will find some benefit to it, but for everyone else, PCIe 4.0 doesn’t do much on its own that will really be felt for the time being.

That said, AMD received massive support from motherboard partners with Ryzen 3000 and the 500-series is likely to be fully featured and offer the greatest overclocking potential for the new CPUs. It’s not going to be necessary to upgrade to – AMD is sticking firm on its promise of multi-generational support for motherboards using the AM4 socket. But there will be some benefits, PCIe 4.0 included, that make it an intriguing option for those looking to make the most of their new CPU.

Computing

Facebook’s crypto isn’t a new Bitcoin, it’s Disney Dollars for a new world order

Facebook has already secured tens of millions in investments for its new cryptocurrency for Facebook known as Libra. The platform is still being developed, but has already brought in backing from Visa, Mastercard and PayPal.
Computing

Intel’s rumored price war against rival AMD could be a big win for gamers

With Intel looking to take on AMD with a new pricing strategy, the biggest winners of the silicon price war will be PC users and gamers. If reports are accurate, Intel plans on slashing CPU prices by as much as 15 percent.
Computing

PCI Express 6.0 is coming in 2021, and it’s already overkill

The PCI Special Interests Group began laying out the specifications for its next, next-generation motherboard socket: PCI Express 6.0. It will double bandwidth again and offer some clever efficiency-boosting technologies.
Gaming

PS5 rumored to be more powerful than Xbox’s Project Scarlett

A rumor claiming that the PlayStation 5 will be more powerful than Xbox's Project Scarlett surfaced before the official reveal at the Xbox E3 2019 briefing. Now that we have more information, let's compare the two systems.
Deals

Apple-refurbished MacBooks and Mac Minis get big price cuts for grads

Deals on Mac computers are hard to come by outside of seasonal sales, so your best bet might be to buy refurbished. These professionally renewed Mac deals are a sure way to save big on Apple computers that look, feel, and work like new.
Deals

The best 4th of July sales 2019: Best Buy, Home Depot, and REI

Whether you're looking for price cuts on mattresses, major appliances, kitchen gadgets, outdoor gear, and just about anything you can think of for summer, there's bound to be a sale with your name on it.
Product Review

The Asus ProArt PA90's steam-engine design speeds past the trash can Mac Pro

It may try to fill the void left by Apple’s aging Mac Pro, but don’t call Asus’ compact ProArt PA90 workstation a trash can. Though this desktop takes inspiration from the Mac Pro’s minimalist design, it brings its own steam…
Computing

Microsoft reportedly releasing foldable Surface with 9-inch screens next year

Microsoft is reportedly planning to roll out a foldable Surface as early as the first quarter of 2020. The device, code-named Centaurus, is said to feature two 9-inch screens, Windows Lite, and Android support, according to IHS Markit.
Computing

The guy who invented USB finally admits it’s annoying to plug in

The man behind the team that created USB has finally acknowledged that the design has caused plenty of frustration over the years. But he insists there was a good reason for building it in the way that he did.
Computing

An all-new, redesigned 16-inch MacBook Pro could launch in September

More news has surfaced that Apple’s redesigned 16-inch MacBook Pro could arrive this year at the company’s September event, featuring an all-new design and high-resolution display.
Computing

Powerful upgrades turn 4th-gen Raspberry Pi into a more capable $35 desktop

The Raspberry Pi 4 is the most powerful Raspberry Pi incarnation to date, making it an even more capable alternative to your desktop PC. Equipped with a more powerful processor, this desktop could be yours starting at $35.
Computing

The MacOS Catalina public beta is live. Here’s how to download it

Apple's latest MacOS update, known as Catalina, is finally available for developer preview, which means if you're willing to pay a little for the privilege, you can be one of the first to try it out.
Computing

MacOS Catalina has arrived. Here are the 5 best features you can use right now

As of Monday, June 24, Apple has released the public beta of its newest MacOS, Catalina. Here are the five best features to expect from MacOS Catalina, including the trio of apps expected to replace iTunes.
Computing

Apple has a plan to save Mac gaming, but it’s not the one you want

The Mac isn’t known for being a game-friendly platform, but Apple hopes to change that in the coming months and years. The thing is, its plan may not be quite what you were hoping for if you’re a Mac gamer.