From what I can find, Intel has only posted efficiency projections for Intel 4 and Intel 3, but there's no path to 2x in sight.We'll need Meteor Lake or Arrow Lake to hopefully improve those aspects. Those future CPUs could actually be faster and more efficient than RPL-R, rather than just incrementally faster... or maybe just slightly faster but half the power? I guess we'll see when those launch.
Based on that, we can work out that the same design @ ISO-performance would use 70% of the power on Intel 3 vs. Intel 7. Although that sounds like we're getting close to your "half-power" figure, Intel 20A would need a 41% perf/W jump to get there. And don't forget, that's @ ISO-performance. If you want more performance, some of those power-savings will go out the window!
However, a leak claims Arrow Lake will reduce PL2 to 177 W. So, you should indeed see some improvement.
Intel Arrow Lake-S CPU power limits: 125W PL1, 177W PL2, and 333W PL4 on the way
Intel Arrow Lake-S alleged power limits teased: 125W baseline power, while unlocked 'K' series CPUs have a PL2 rating of up to 333W.
www.tweaktown.com
Finally, leaked benchmarks show performance projections putting Arrow Lake up 7% to 20%, with the median falling around 11% or so, relative to the i9-13900K.
Intel Raptor Lake Refresh, Arrow Lake CPU Performance Projections Leaked
Arrow Lake's up to 21% faster than Raptor Lake with an over 2X faster iGPU.
www.tomshardware.com
In fact, if you look at the middle slide of that article, the single-threaded SPEC2017 tests show only a meager 3% to 8% improvement over the i9-13900K, within the same power limits. That suggests most of the improvement is in energy-efficiency: via some combination of improving throughput of the E-cores and improving efficiency of the P-cores.
What's worrying about those projections is that they supposedly used a PL2=253 W. So, maybe the actual multithreaded performance will be less, if the 177 W rumor is true.
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