Question Ram compatibility

[MittronR32]

I'd like to buy x2 16gb sticks of ddr5 5600 ram but i already have x2 16gb sticks with 4400mhz. can i use all 4 of them for a total of 64gb?

 

[Nine Layer Nige]

Im guessing that if it did run all 4 sticks, then it would only run at a max of 4400mhz anyway so would be no benefit in buying 5600mhz.
So, I think it would be better to sell the 4400mhz sticks and buy a 64gb set of 5600mhz so you know its compatible.