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do not make assumptions based on a lack of hard data. >> If you don't have data for multiple years of a system or multiple chips >> in the system, leave it off your quirk list. They can always be added >> later when the data is available. > > Specifically for GPD, the userspace implementation has been tested on > all generations. It is fine to choose a (lower) limit that works on > all of them. The thermals did not change between generations. > Saturation above 20W means that there is little difference between > 22W, 25W, 28W, 30W, etc. If there is doubt, going lower is fine. Even > if one device can do 5W more it does not matter (but the chassis, > battery, and cooler are exactly the same; only the board was revised > for the new SoC). > > 8-20W is the sweet spot for these APUs. 8W and 15W are sane for > low-power/balanced. The only question is how close to 30W should be > the maximum and where performance should point to. This version does > 25W for performance. 20W might be better for daily use until AC/DC > detection. > > We do not need to complicate things. All this driver needs to do is > expose a slider from 4-30W. This covers 6800-HX370 for all vendors and > matches user expectation. AI Max will need further research as I do > not have a lot of data on its performance curve. Ayaneo had some drops > between 2022-2023 that had lower TDP limits, but there is less than 1k > units in existence. User expectation and reality aren't necessarily the same. Performance is tied to a thermal design. A user might want to run a handheld at the max performance, but max performance is not purely a function of the APU. It's a function of the APU + cooling solution + power distribution. That's why I have been saying there need to be different values for different parts, and you can't make assumptions year to year. Even if the external chassis plastics are identical, a different fan or heatpipe might be used and those are non-trivial impacts. The values used should be calculated by performance measurements of the entire solution in a thermal chamber. I know you're not going to be able to do that, but that's what manufacturers /should/ be doing.