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Why is the RT wattage lower than the non-RT one?

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As the title says, I encountered a peculiar thing in my RX 6700 XT's behaviour: in the Cyberpunk 2077 game, I notice about 5 to 20 percent lower power consumption if I enable ray tracing which is counter intuitive.

This isn't affected by the OS version, driver version or whatnot. I'm inclined to imagine that the RT cores are so overwhelmingly slow that the raster block has to wait for it to do its job which ultimately results in raster block "slacking" and my GPU hitting lower power values.

Am I right? Any way I check this?
 
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I don't think there are "tensor cores" in AMD's RDNA2/3 designs. It relies on the texture units fills & syncing. Yes, it does have to wait, because the RT cores themselves are part of the same shader compute block which includes the textures units. you should be able to see them on both the RDNA2/3 diagrams on TechpowerUP reviews when they released.
 
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My guess is with RT the card gets lower FPS and so other parts of the card are under less load.
I noticed the same thing with stability tests on my old 660 Ti in FurMark. If I turn AA up, power consumption goes down.

I bet if you set a FPS limit that is lower what the card does with and without RT and check again, things should look different.
 
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