No input signal on monitor after adding another black 8GB Ram to second slot. It has the same mhz, latency etc. Why it doesn't work? PC works again after removing it. :
8GB (1x8GB) DDR3 PC3-12800U DDR3 Non ECC Desktop DIMM Memory DELL HP Lenovo Acer – WallBuilders
Amazon.com: OWC 8GB (2 x 4GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with Mac Mini (Late 2018), 27" and 21.5" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S08P) : Everything Else