nVidia GPUs have something, that is used by various software makers to create a sensor that they call "PerfCap Reason", it tells you why the GPU is throttling (examples: lack of usage, power limit, overvoltage protection, undervoltage protection, etc...)
From what I could find, AMD cards also support this, more or less...
First, there is PowerPlay, that obviously knows why it is throttling (otherwise it wouldn't throttle in first place). So querying it would be interesting, if possible.
Also I found out AMD GPUs have a communication protocol (that chip designers even advertise that their chip is "AMD compliant" when their chips can use the protocol), that are used by OC software, and theoretically according to the datasheets I found of some common VGA VRM controllers, can tell you when voltage protections of different kinds were triggered, or tell you about some event logs.
So what I want to know is: How I get that information? It would be useful for end users to troubleshoot their system, would be useful for people that make softeare like "GPU-Z", would be useful for devs to figure weird performance issues in their games and benchmark software, and so on...
