Yeah, I edited my original post, but I was slow hitting save! I guess that was perhaps me misinterpreting what I was hearing due to wishful thinkingfrom my understanding, the CPU and chipset can run ddr4 that doesn't mean that a motherboard company is going to make a board with both slots, cause even with the pinout being the same 288 pins the traces off of the slots is not so you can't have one slot that runs both.
tomshardware says DDR5 RAM sticks will have the same number of pins, 288, as DDR4 DRAM modules. The pin layout, however, is different Which means you won't be able to use DDR5 modules on a DDR4 slot
They are not interchangeable, its one or the other and from my understanding only lower end boards will support ddr4.I thought I saw that the mid to high end motherboards were likely to support DDR4 and DDR5.
If that is the case, and I know you tend to buy higher end motherboards, why not go that route? Keep your 64GB Dominator and run them with the new CPU, and then upgrade to DDR5 when the dust settles and you can determine if it is worth it for the cost?
Edit: I see that you have the Z690 HERO in the title, and that is DDR5 only. So my suggestion would require a different motherboard, if they exist. Researching a little, and I'm not sure this suggestion is an option. Alder Lake supports both DDR4 and DDR5, but most of the Z690 motherboards I could see support DDR4 OR DDR5. Not both on the same board. So maybe I dreamed that...