New AMD B550 Motherboards Are Incompatible With Earlier Ryzen CPUs
AMD has announced its new B550 motherboard family as the follow-on successor to the B450, with new features like PCIe 4.0 and multi-GPU support, though that feature is of questionable value these days. Still, it’s an update to the B450 that brings a faster interface — as well as a new wrinkle for AMD fans.
When AMD launched Ryzen in April 2017, it declared it would support Socket AM4 at least through 2020. Many fans read this as a promise that AMD would support the same motherboard chipsets for the duration of the AM4 socket. That difference of interpretation has caused some confusion about what kind of support matrix AMD would offer for Ryzen motherboards as the CPU family evolved.
With the launch of the B550, AMD is making a break between current and future CPU support. The following chart explains which motherboards support which CPUs, now and in the future:
This chart indicates that AMD Ryzen 3000 CPUs aren’t supported on X370, but that may reflect the fact that support is on a case-by-case basis for that platform. In any event, what we see here is that there will be no support for future AMD Zen 3 microprocessors on either the 300 or 400 series boards. If you want a platform that’s guaranteed to be upgradeable in the future, you’ll need to move to X570 or B550 to do it.
How much upgradeability will that get you? That’s uncertain. We don’t know when DDR5 will be introduced, and AMD is expected to use AM4 until it is. It seems likely we’ll see at least one more DDR4 cycle after Zen 3, and AMD has promised to continue to keep improvements rolling in, generation-on-generation. So far, the company has done an excellent job delivering on those promises.
Did AMD Deliver on the Spirit of Its Promise?
AMD may not have promised to provide chipset support through 2020, but plenty of people heard the statement that way. So, did the company provide the upgrade path it implied existed? I would argue yes.
In April 2017, a top-end Ryzen system consisted of an X370 motherboard and an eight-core Ryzen 7 1800X CPU. Today, just over three years later, that same motherboard is likely capable of stepping up to a Ryzen 9 3950X. In well-threaded tests, the 3950X can hit over 2x the speed of the 1800X. Even in single-threaded tests, the 3950X is often 1.25x – 1.35x faster than the 1800X.
None of this automatically makes a 3950X a great upgrade for an 1800X owner — if you don’t have any workloads that can scale up to 12-16 cores, you aren’t going to see the same benefit as someone who does.
This isn’t the first time we’ve seen a motherboard deploy with support for, say, dual-core CPUs, only to add support for quad-core or even six-core chips as those solutions became available, so I can’t say that Ryzen 7 delivers a completely unprecedented upgrade. But it’s certainly one of the best overall upgrade values that we’ve historically seen. Realistically, I’d expect an X370 system rebuilt on Ryzen 9 3950X to still be an effective performer in 4-6 years. Desktops don’t age like they used to — I’m typing this on a Core i7-4960X that’s continued to provide perfectly adequate performance for gaming and desktop work. Even if a person swaps out in 2024, that’s a seven-year lifespan for the AMD system.
Granted, it is a little annoying to have to keep track of all the different support diagrams, so make certain you know what you are getting into before you buy. It’s not clear how many more product cycles we’ll see on AM4, but the relatively slow rate at which desktops age makes this much less of an issue than it used to be.