Unplug the system Remove the heatsink CPU fan and push down gentle on the CPU a few seconds. Then put back the heatsink and CPU fan back on. If that still doesn't work you might have 1 or 2 faulty devices.
1. CPU
2. MOBO
or 3. RAM
Somehow on these DELL OP models from 200 right up still have this sort of problem. I remember replacing on for user who told me when she was in Windows the system would just shutdown or reboot. Replace the MOBO still did it replace the CPU seem to fix it. But you really can't tell which one. I just order what I need the user never put in service request again.. Case solved..
Do a file search for *.dmp files and delete them off your system You don't need those anymore. You can also turn off this feature under the System Devices Manager under advance, then startup and recovery.