Before upgrading the processor, I would suggest you to perform diagnostics on the system to check if it is a hardware issue. Restart the system and tap F12 for advance boot options. Select "Diagnostics" or "Utility Partition" for diagnostics. Please refer to the link mentioned below for the error codes:
If the test pass, please check the system in safe mode by tapping F8 on the dell logo.
Also, you may troubleshoot the system by performing clean boot:
Thanks & Regards