I want to install 2 SSDs on the Z270F: 1 will of course be the boot drive with Win10 and all program files on it; the 2nd will be strictly a backup that I periodically clone from the 1st drive. I already have an XPG SX8200 Pro M.2 2280 PCIe SSD for the main drive, but I've been reading about some restrictions on the type of SSD I can use in the slot closest to the CPU, and want to make sure I don't buy one that won't work. I also want to make sure that cloning will work as I intend as well, that there's nothing odd about doing it with SSDs vs normal HDs.

I'll also have 2 4TB HDs in the system for all documents, files, movies, etc. that will function the same way... 1 in use and the 2nd one a cloned drive as a backup.

Are there any restrictions I should be aware of as to what SSD I can use in the slot closest to the CPU, and will cloning work without issues? Any problems you can help steer me away from or advice would be greatly appreciated. I've been building my own PCs for over 20 years, but this is my first time using SSDs.

Edit: Could I just use the same exact SSD for the 2nd slot? The Adata XPG8200 Pro 1TB.