Solving Network Problems - HP EliteDesk 800 G4 SFF Maintenance And Service Manual

A new device is not recognized as part of the system.
Cause
USB ports on the computer are disabled in Computer Setup.
Computer will not start.
Cause
Wrong memory modules were used in the upgrade or memory
modules were installed in the wrong location.
Power LED flashes Red three times and then white two times.
Cause
Memory is installed incorrectly or is bad.

Solving network problems

Some common causes and solutions for network problems are listed in the following table. These guidelines
do not discuss the process of debugging the network cabling.
98 Chapter 6 Troubleshooting without diagnostics
Solution
To access Device Manager in Windows 10, type device
manager in the taskbar search box, and then select Device
Manager from the list of applications.
Run the Computer Setup utility and ensure that Device available
is selected for appropriate USB ports under Advanced > Port
Options.
Solution
1. Review the documentation that came with the system to
determine if you are using the correct memory modules and
to verify the proper installation.
NOTE: DIMM1 or XMM1 must always be installed. DIMM1
must be installed before DIMM2, and DIMM3 must be
installed before DIMM4.
2. Observe the beeps and LED lights on the front of the
computer. Beeps and flashing LEDs are codes for specific
problems.
3. If you still cannot resolve the issue, contact Customer
Support.
Solution
CAUTION: To avoid damage to the DIMMs or the system board,
you must unplug the computer power cord before attempting to
reseat, install, or remove a DIMM module.
1. Reseat DIMMs. Power on the system.
2. Replace DIMMs one at a time to isolate the faulty module.
NOTE: DIMM1 or XMM1 must always be installed. DIMM1
must be installed before DIMM2, and DIMM3 must be
installed before DIMM4
3. Replace third-party memory with HP memory.
4. Replace the system board.