5X5CX62,   The server and controller will both support using 512e and 4k drives, now with that being said you can mix 512 and 512e drives in the same virtual disk, but mixing 512 and 4k drives in a virtual disk is not allowed. So with you creating a separate Virtual Disk for the 4k, you will be fine.   Hope this helps.
We have an existing RAID 1 group of two 512e 300GB 10K SAS drives controlled by a H730. Current plan is to add six 10TB NLSAS drives and create a RAID5 with one HS.   I wonder whether it would be a terrible idea to purchase 4kn drives for their marginal efficiency increase and potentially run into problems since existing drives (although in different RAID) are 512e.   Any input is highly appreciated.
Mixing 512e and 4kn drives in R730?