AMD has supported the AM4 platform for almost a decade. I wrote "has" because the company continues to roll out new processors for the socket, allowing those with older AMD motherboards to continue using their systems without upgrading and replacing multiple parts. This not only enables consumers to get much more from their PC but also helps combat e-waste. AMD plans to do the same with AM5, noting support will continue through 2027 and likely beyond.

Although this is fantastic for consumers since it means we have more years between socket launches, which require new motherboards, it does provide plenty of hurdles for AMD engineers to overcome. We put forward some questions to AMD's Sourabh Dhir, Director of Product Management, to see how the company is able to get much more from each socket generation and what challenges teams face when planning roadmaps and building new CPUs.

Supporting AM4 beyond a generation

10 years is a long time in the socket world

AM4 launched in 2016 and was initially supported until 2022, which is when the Ryzen 7000 series launched on AM5. It seems AMD made the move primarily because of the addition of DDR5 and PCIe 5.0. This required an architectural shift and simply wasn't compatible with the AM4 socket due to increased speeds on the memory front, as well as more bandwidth with I/O and expansion. It's amazing to know that if you purchased a motherboard in 2017 and still use the PC with the same part, you can upgrade to a processor released as late as 2025 with the 5500X3D.

Sourabh Dhir explained the goals behind AM4 and how AMD wanted to break the cycle of frequent socket replacements. "When we introduced AM4, our goal was to break the cycle of frequent socket changes every couple of generations. We wanted to create a long-lasting platform that could adapt to evolving industry standards such as PCIe and memory speed advancements. With that vision, we aimed to support AM4 for as long as it remained viable in the market. What we didn't fully anticipate was just how long and successful its run would be."

Another issue with supporting a socket for so long is the firmware. "The BIOS is limited by its size, which is why we pushed for larger flash memory banks on AM5. Along with that, supporting faster memory within the same socket footprint isn’t straightforward; it requires careful engineering and innovation. The easier path would be to introduce a new socket, but maintaining compatibility demands advancements in areas like memory controller design, signal integrity, and platform-level optimizations. These efforts are what allowed us to enable socket longevity."

Looking to the future with AM5

Supporting the platform for longer

AMD's ability to continue supporting the same CPU socket for so many years is yet another blow to Intel's approach, which has still only been able to support a few CPUs in comparison. Since the launch of AM5, Intel has already gone through two sockets. AMD looked at AM4 to see what lessons it could take from the older platform to continue pushing platform longevity. "We definitely learned a lot from AM4. To put it in perspective, no one had ever attempted to make a socket last as long as we did with AM4. It was generally accepted that a platform would last around two years, with four years being the upper limit."

"Another significant shift was setting the expectation with our motherboard partners to support a platform for nearly a decade. Kudos to those partners who continue to deliver BIOS updates for boards they originally sold back in 2018." Although one would assume supporting the same socket (and chipsets) for longer would hamper sales for AMD, the company saw quite the opposite. "The fact that we are still selling AM4 processors proves the opposite of what some might expect. AM4 continues to be a great way to add value for our customers, foster loyalty, and create more opportunities to sell product. Many users have been able to upgrade their systems with multiple processors over time, all without needing to replace their motherboard or memory."

It's also interesting that Dhir touched on using both AM4 and AM5 as a broader range of product lines for consumers, instead of fully closing up AM4 to focus on the newer technologies. "This approach also offers more choice and a broader range of options. It also allows us to address different parts of the market with AM4 and AM5, each serving distinct price points and customer needs." There are other ripples too, including CPU coolers and RAM, since supporting the same socket for longer means system owners don't have to replace other parts as well as the motherboard. If you're splashing the cash today, you won't FOMO or regret in a few years.

Achieving the seemingly impossible

Working within designed constraints

Unsurprisingly, supporting the same socket across multiple generations introduces various technical issues. This required AMD to think outside the box and come up with some creative ways to solve these problems. "Supporting the same socket over time comes with both advantages and trade-offs," explained Dhir. "On one hand, the platform matures and becomes a known quantity from an engineering standpoint. The initial growing pains of a new platform are behind us. On the other hand, you're constrained by the design decisions made at the socket’s inception."

"You can't simply add a pin or make structural changes the way you could with a new socket. This really highlights the incredible foresight and skill of our engineering team, who continue to extract more performance and functionality from the platform despite having fewer levers to pull compared to a fresh socket design." This led us to question what AMD has planned for AM5, since the company continues to roll out previous-generation CPUs with some of the improvements we've seen in more recent SKUs. Although AMD promised to support AM5 through 2027, Dhir explained that the goal is replication, within reason.

"Our goal with AM5 is the same as it was with AM4 — to deliver maximum value to users who invest in an AMD platform. As new technologies emerge, we will evaluate the best way to integrate them, either by extending support for existing platforms or by introducing a new socket when needed. At the same time, we remain committed to pushing the limits of performance through ongoing improvements in firmware, chipsets, and overall platform design." Next up is Zen 6 with the same AM5 socket, which is expected to be an evolutionary refresh as opposed to a complete revolution.