ASUS GPU Tweak is being updated very often lately (more than AB from what I can tell).
AB is using the latest Riva Tuner (last remaining company to do so, I think) as the competition felt a sell out to MSI and blackmail business tactics from Riva Tuner to continue its 1st grade support.
Many copy cat utilities will function the same (compatible) using official AMD/nVidia set driver programs to monitor the GPU, CPU, VRAM, TEMP, etc activities. The skins may look similar mostly for familiarity and not copy cat programming.
I personally like AB presently still. I predict ASUS GPU Tweak will compete well in the near future with all their effort. I am sure EVGA Precision will fare well too.
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