AMD claims that the new Ryzen 9 7945X3D with a whopping 144MB cache is the fastest mobile gaming processor on the planet, and that it’s more than 15 percent faster than the Ryzen 9 7945HX on average. It has 16 cores, 32 threads, up to 5.4 Ghz boost speeds and 55W+ TDP. The CPU is built on the Zen 4 architecture.
It’s because the 7900 and 7950 are using an “old” naming scheme and the 7945 is using a new naming scheme.
One of the side effects of this is that bigger number no longer necessarily means better, especially if you’re comparing between architectures