Hi rwiley, welcome to the HP Forums. From what I gather, you are saying that you still get thermal shutdown errors even after replacing the system fan and CPU? It sounds like you have done all reasonable troubleshooting. The only other thing I can think of is, to see if it will allow you to restore your BIOS: Restoring the BIOS
Here is the original troubleshooting for the original issue, make sure you covered everything: Troubleshooting an Overheating and Auto Shutdown Issue
If the error still occurs if your replacement processor is functional, it is most likely a system board issue.
Let me know how it turns out.