Most likely the RAM is incompatible.
Mixing RAM brands/specs commonly results with that problem.
RAM should be installed in matched pairs to avoid that problem.
PNY is not a recommended brand and if your PC is OEM, Crucial is the better brand choice to help insure compatibility: RAM Memory Upgrade: Dell, Mac, Apple, HP, Compaq. USB drives, SSD at Crucial.com
Pre- Built Brand & Model Number
Custom Built- Brand & Model of Mobo-CPU-RAM-Graphics-PSU.
Will the PC boot and run properly if the new RAM is removed?