The hardware SEL is a function of most server motherboards. The baseboard management controller (BMC) records hardware events, including most health events, into an area of the motherboard non-volatile memory. In other words, this event log can be retrieved even after the system has been cold booted. A CMOS clear is likely to delete all of the events.
The hardware SEL should not be confused with the Windows System event log, which records Windows events. The hardware SEL will record things such as power events (power on, power off/loss of power, power redundancy events etc.) and faults such as fan issues, memory ECC events, or some motherboard errors such as PCI Express bus faults.
Motherboard manufacturers such as Intel provide utilities to display or save the SEL log. Utilities available depend on the motherboard model. Use the DOS or EFI mode version when Windows is not operating. For most models, a Windows version is available which allows SEL events to be retrieved while Windows is running, after the installation of an IPMI management driver.
While DOS mode tools are available for some platforms, use of EFI tools is preferred as you do not need to prepare a Windows 98SE DOS bootable pen drive.
You will need to download the SEL viewer utility for either EFI, DOS or Windows. Always consult the motherboard or platform download pages for updated downloads.
On all Windows systems you need to install the correct package (32-bit / 64-bit) in order to install the correct IPMI driver. The IPMI drivers are included in the distributions. Note that the Window's SEL log utility requires Java to be installed if you want the GUI displayed. Using the command line option to save the log does not require Java.