Last week in Sonoma, AMD unveiled new details on its upcoming CPU architecture, codenamed Zen. For the past 16 years, AMD has relied on a combination of Greek (Athlon, Phenom) and Latin-derived (Duron, Opteron). More recently, it’s used the old “FX” moniker from its high-end Athlon 64 consumer hardware to market Bulldozer and Piledriver-derived CPUs. Going forward, Zen will be marketed under the “Ryzen” brand name (pronounced RYE-zen).
AMD didn’t just unveil the branding — it gave some additional details on the CPU’s minimum clock frequency, total L2/L3 cache, and new capabilities as well.
When AMD tested Zen against the Core i7-6900K back in August, it locked both chips to 3GHz. This raised concerns that AMD might run at a significantly lower clock than Intel does, further harming the company’s ability to compete effectively. We now know that’s not going to happen — AMD isn’t revealing exact SKUs yet, or even its absolute minimum base clock, but the company has confirmed that it will offer an eight-core chip with at least a 3.4GHz base clock. The 20MB of cache doesn’t specify between L2 and L3, but that’s easy to break down — we’ve already been told that each CPU complex (CCX) consists of four CPU cores backed by 8MB of L3 cache. Two CPU complexes = eight cores and 16MB of shared L3, with 512KB of L2 for each CPU core. Each L3 cache appears to be unique to its core complex; it’s not clear what the penalty hit is for retrieving data stored in a different CCX’s L3.
There’s a new platform update coming as well, with support for PCIe 3.0 and USB 3.1 Gen 2. AMD has been contracting with Asmedia for its southbridge designs and we expect that will continue. AMD continues to insist that Zen represents a 40% improvement in IPC over Excavator, but it still hasn’t shared details on how it arrives at that calculation, or whether that includes the performance boost from its new symmetric multithreading technology SMT.