2666MHz CL16 vs 3200MHz CL22 RAM: Slower stick wins — system runs at the lower speed and timings

The motherboard forces all sticks to the slowest stick’s JEDEC profile, so your 2666 CL16 plus 3200 CL22 will run at 2666 MHz with the 8GB stick’s timings. Dual-channel only works for the first 8GB if the 8GB stick is single-rank; the rest runs single-channel. Fine for everyday use, but you’re leaving performance on the table — consider a matched kit for memory-sensitive work.