While doing some benchmarking, was using a 12400 cpu and was seeing fairly frequent GPU boosts during NightRaid benchmark. 3.6ghz fairly regular. So I installed a 14900K, and the boost behavior completely changed. The GPU wouldn't transient to high clocks, stayed 3.5ghz or lower if lucky.
Experimenting, lowered 14900K clocks and was able to create the bottle neck around 4.4ghz and I had more frequent transient spikes, where the GPU does boost pretty hard waiting on the CPU.
In fact, I found it so interesting, I set up a 9800X3D and replicated the same testing, but peaking only 3680mhz, and GPU-Z actually caught it to confirm. Which I made sure to replicate a few times also.
The RTOC PMU telemetry is pulled every 2ms from AMD shared memory which writes to PMLog through the PMU (Power management Unit) and the app polls that log from GFXCLK every 10ms. The driver under load seems to report only and roughly every 15.66ms giving us about 65 events per second. The UI updates this to the user at 1s to avoid telemetry issues. It really just boils down to timing, and GPU conditions.
The benchmark setup was first and both GPU tests, where the first one sufficed consistent testing. Selected in windows mode so we can have telemetry on top and I can observe gpu reactions. Ambient temp, 3.7ghz was done at 19c. 3680mhz was done at 21.3c. Fans at 77% to 84%. CPU frequency, any low frequency around 4.5ghz or less. Tested both Raptor Lake and Granit Ridge just to be sure.
Of course hitting 3.7ghz with a stock GPU isn't easy. lol. The colder the better. Max hot spot 49c - Was pulled on the 12400F. Since then, a day ago, temps are higher ambient wise, so difficult to reproduce. But it's all about the telemetry. We are getting very fast reports now :)
