When AMD launched its Ryzen 7000-series CPUs, PC builders were met with teething problems – the memory support was lackluster, memory training times were intensely long for first-time POST, over-voltage issues were causing CPU socket damage in edge cases, and the platform price was simply too much to swallow for most PC builders looking to upgrade an existing PC.
Pictured: an Arsenal PC custom build featuring Gigabyte-themed components and Socket AM5 (Ryzen 9 9950X3D + four sticks of 32GB DDR5)
That was 2022, this is now. So what has changed in the past 3 years since AMD launched Socket AM5? We have new chipsets, two new generations of CPUs, 3D V-Cache… many things are different today than they were at the 2022 launch. One thing that has not changed in the slightest – AMD’s I/O chiplet. Inside every Ryzen CPU for both Socket AM4 and AM5 is an I/O chiplet which handles the communications between the CPU compute cores, RAM, its directly-connected PCIe slots, and the motherboard’s chipset. When Socket AM5 launched, a whole new I/O die was designed for the updated DDR5 standards. It hasn’t been updated since.
In practice, this means RAM support has only improved marginally with BIOS updates to motherboards. Choosing the correct RAM for your Ryzen PC build is just as important today as it was 3 years ago! The two most important points we can make about this from the professionals at Arsenal PC are:
- Choosing RAM for your Ryzen PC that features AMD EXPO timings is far more likely to result in a stable, working system than choosing RAM that only advertises Intel XMP compatibility.
- Knowing what speed AMD officially supports for your RAM configuration is key to troubleshooting any RAM-related issues.
Pictured: an Arsenal PC custom build featuring Gigabyte-themed components and Socket AM5 (Ryzen 9 9950X3D + four sticks of 32GB DDR5). In the foreground are two packages of DDR5 RAM.
Note that the RAM kit on the left only advertises itself as Intel XMP 3.0 Ready. That memory kit from G.Skill is not stable in any of our AMD Ryzen 7000 or 9000 test systems! G.Skill makes a version of the same RAM kit featuring both Intel XMP and AMD EXPO compatibility, which is the Trident Z5 Neo. That small detail is the difference between a stable, working Ryzen build and one that gives countless intermittent issues at POST. (A Silicon Power kit is shown on the right, which features small logos for both XMP and EXPO towards the bottom left corner of the packaging.)
Since AMD has not updated its I/O die since 2022, the officially supported RAM speeds are lower than most people expect. With two sticks of DDR5, Ryzen 7000 CPUs only support 5200MHz RAM officially, and Ryzen 9000 CPUs support 5600MHz officially. Anything above that is considered overclocking, and not officially supported by AMD. (Most of the time, a small amount of overclocking works OK, but your mileage may vary.) With four sticks of DDR5 though, the official supported speed is only 3600MHz. That’s not a typo, and that applies to both the 7000 and 9000 series CPUs. In our own internal testing, we’ve validated that with 4 sticks of RAM that 3600MHz is a fail-safe guarantee, and only a few CPUs can exceed that while remaining stable.
Long story short, choose an AMD EXPO compatible kit with speeds that closely match your CPU’s capabilities, and be sure your BIOS is fully updated to the latest version!