A data center technician is troubleshooting a server that is overheating and shutting down intermittently. The server is a 2U rackmount with six fans at the front and a power supply with an integrated fan at the rear. The technician checks the ambient temperature (72°F) and verifies that the server intake temperature is normal. The server's system logs show 'CPU temperature threshold exceeded' before each shutdown. The technician has replaced the thermal paste on the CPU and reseated the heat sink, but the issue persists. Which of the following should the technician do NEXT?