Dell Technology Guide
Page 275
...R O R - CPU fan failure. Replace the CPU fan (see the Service Manual for your computer for more details. C P U F A N F A I L U R E - Possible HDD failure during HDD boot test (see "Contacting Dell" on page 337 for assistance). System Messages for Desktop Computers NOTE: If the message you can use the status of certain features. If...various keyboard status lights displayed, see the Service Manual for your computer or search for the topic on the Dell Support website support.dell.com. Troubleshooting 275 Possible motherboard failure or RTC battery low. FOR MORE ...
...R O R - CPU fan failure. Replace the CPU fan (see the Service Manual for your computer for more details. C P U F A N F A I L U R E - Possible HDD failure during HDD boot test (see "Contacting Dell" on page 337 for assistance). System Messages for Desktop Computers NOTE: If the message you can use the status of certain features. If...various keyboard status lights displayed, see the Service Manual for your computer or search for the topic on the Dell Support website support.dell.com. Troubleshooting 275 Possible motherboard failure or RTC battery low. FOR MORE ...