It is a strange result. 4C/8T CPU in practice is more like 5C/5T running games. With one thread running linux OS, one running hypervisor/VM, one running Win7 in the WM, plus extra work in the CPU package with iGPU going ... still faster and cooler for me than having full CPU on game with a pair of high-end GPU cards.
Easy enough to just try it yourself, enable iGPU (and install iGPU drivers, if you haven't), disable PCIe, launch the game. If it doesn't work for you then reverse your changes. It's only a pain if you have to switch your monitor cable each time.
Adaptive voltage has advantages, uses more power when needed, uses less power overall, with good cooling it consistently sustains higher clocks. I prefer to not use it because I don't trust "smart" automation and I don't like variance. And I'm "softcore" ROG, I don't like pushing parts to their extremes because they tend to just end up requiring more time and attention and burning hotter and brighter and burning out faster. Adaptive voltage is a popular choice for good reason, and a good argument can be made for adaptive voltage actually being gentler on your CPU in the long run, but the tradeoff for a few hundred more MHz I don't really need is not for me.
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