Memory DMP files can be safely deleted. These files are not necessary for running Windows in any way and deleting them will not harm a computer.
Windows creates a text memory dump file or DMP file, when an application or program crashes. In this file, it records the stop message parameters and data, the processor context, the kernel context for both the process and thread that stop and the kernel-mode call stack for the thread that stopped. IT professionals and knowledgeable computer users can open and read these files to diagnose and debug a program or computer that has crashed.