I don't think Phoronix had idle consumption numbers for Linux unless I missed it? I'd be curious if it's a problem in Linux as well as windows, as I do believe that it's either a firmware or driver bug. One thing pointing to that is that ComputerBase had much lower idle power numbers with a multi-monitor setup (power consumption in various reviews seem to show differences depending on different monitor models connected) but it still went significantly higher with video playback:
https://www.computerbase.de/2022-12/amd-radeon-rx-7900-xtx-x...For power efficiency, considering that Ada is a monolithic TSMC N5 variant (4N) die while Navi31 is a combination of N5 + N6 for the 6 MCDs, maybe it's not so surprising... One thing to note is that historically, GPUs companies are almost always pushing towards the far end of the VF curve for their top-tier cards. For example, while the 4090 has gotten tons of flack for it's power consumption, cable melting, etc, a Korean review site did testing on power limiting and undervolting while gaming [1] and found that you could basically switch to an 80% Power Limit (only 21W of power savings though) and lose <1% performance. Alternatively, with a slight undervolt, you could shave 58W of power consumption while lowering performance by 1.2%, or 95W (from the 347W stock) with 4.6% lower performance.
As to the smart move, IMO from a price-perf perspective, all of these new cards are a bit out-to-lunch. For gaming, high-end last generation cards (like a 6800XT at $600) will get you to 4K60 on almost all AAA titles and are a fraction of the price of the Radeon 7000 or RTX 4000 series. Also, while I'm a big fan of open source drivers, those doing ML are basically forced to buy Nvidia atm.
[1] https://quasarzone-com.translate.goog/bbs/qc_plan/views/3068...