Xe3 on Pantherlake seems to indicate 25-30% perf/watt improvements over Xe2. That's actually ok. It won't be multi-generation behind anymore. Maybe just 1 year. If we take TPU efficiency results and extrapolate from B580, it would be RDNA4 class.
Pantherlake improves greatly on the Depth Writes micro bench test, which has to do with hidden surface culling. It'll utilize bandwidth and memory subsystem better.
Mesh Rendering test improvement is for high polygon count workloads.
Also variable register allocation and 25% increase thread counts per core improves utilization, which is a known problem even for Battlemage.
Something interesting:
First things first: Intel emphasized that Xe3 is not based on the Celestial architecture,