Damaged data in CMOS memory or damaged server firmware can causeundetermined problems. To reset the CMOS data, use the CMOS jumper to clearthe CMOS memory and override the power-on password; see “System-boardswitches and jumpers” on page 18. If you suspect that the server firmware isdamaged, see “Recovering the server firmware” on page 152.If the power supplies are working correctly, complete the following steps:1. Turn off the server.2. Make sure that the server is cabled correctly.3. Remove or disconnect the following devices, one at a time, until you find thefailure. Turn on the server and reconfigure it each time.v Any external devices.v Surge-suppressor device (on the server).v Printer, mouse, and non-IBM devices.v Each adapter.v Hard disk drives.v Memory modules. The minimum configuration requirement is 2 GB DIMM inslot 3.4. Turn on the server.If the problem is solved when you remove an adapter from the server but theproblem recurs when you reinstall the same adapter, suspect the adapter; if theproblem recurs when you replace the adapter with a different one, suspect the risercard.If you suspect a networking problem and the server passes all the system tests,suspect a network cabling problem that is external to the server.Problem determination tipsBecause of the variety of hardware and software combinations that can encounter,use the following information to assist you in problem determination. If possible,have this information available when requesting assistance from IBM.The model number and serial number are located on the ID label on the front of theserver as shown in the following illustration.Note: The illustrations in this document might differ slightly from your hardware.ID labelv Machine type and modelv Microprocessor or hard disk drive upgradesv Failure symptom– Does the server fail the diagnostic tests?– What occurs? When? Where?– Does the failure occur on a single server or on multiple servers?156 IBM System x3550 M3 Types 4254 and 7944: Problem Determination and Service Guide
