current buildYes, XMP will work with all 4 slots. Of course, this can vary with motherboards and memory models/speeds.
What are the complete specs for the system in question?
Not sure about your math. 2x8 = 16GB (not 32GB)better choose new 2x8GB (so this will 32GB) or better 2x16?
On dual channel boards 2 ram module configuration is better than 4 module configuration (A320 and B450 are dual channel chipsets).and like title will xmp working at 4 slot, but if not work at 4 slot , speed 2667 vs 3200 not different at gaming and general task right ?