AMD Phoenix 2 Die Shot Appears To Confirm A Hybrid Zen 4 And Zen 4C Design
Now, we have a new leak that would seem to corroborate those earlier leaks and rumors. This one's a die shot that seems to be of the Phoenix 2 processor die, and it comes to us by way of regular leaker HXL on Xwitter, better known as @9550pro. We say "seems to be", but there's almost nothing else it possibly could be, looking at the layout of the components.
Just as rumored, the little chip sports six CPU cores: two full-fat Zen 4 CPUs, and then four compact Zen 4Cs. These are almost assuredly configured in a "big.little" configuration where the Zen 4 cores run at relatively high clock rates, and the Zen 4C cores are clocked lower to save on power.
If you don't know about Zen 4C, check out our coverage of AMD's "Bergamo" CPUs, which are EPYC processors made entirely of Zen 4C cores. The short version is that Zen 4C is exactly as capable as a regular Zen 4 core, just with one-half the L2 cache and a considerably denser design. That makes this chip rather different from something like an Intel processor that has completely different CPU architectures for its P- and E- cores.
The CPU cores seem to share 16MB of L3 cache—one-half that of a typical Zen 4 processor—while the integrated GPU is just two WGPs, equating to four compute units or 256 shader cores. Very smart guys have identified some fourteen lanes of PCI Express connectivity on the die, as well as three display connections, two USB4 connections, and a whole pile of USB 2. For memory, it has a totally-unsurprising 128-bit DDR5 interface.
Interestingly, this chip configuration, with its six cores, twelve threads, and four RDNA 3 compute units, exactly matches the specifications of the Ryzen Z1 processor that is supposed to show up in the lower-end version of the ASUS ROG Ally handheld. That product is still not available at this time, but we think it's a safe bet that the non-"Extreme" version of the Ryzen Z1 will likely use this exact silicon.
It will be fascinating to see how this chip performs compared to the full-fat Ryzen Z1 Extreme, which is based on the original Phoenix processor with eight CPU cores and twelve RDNA 3 compute units. You might reasonably expect it to be a lot slower, but we actually found that Phoenix really wants 35W or more to stretch its legs and flex that big integrated GPU, and that's just too much power for a handheld. The difference between that chip and this little beastie at, say, 15 watts might be a lot smaller than you think.
