[CentOS] What is the System Event Log?

Robert Nichols wrote:

>> My Dell PowerEdge T105 running Centos-5.2
>> has started crashing fairly often (3 times in the last 2 hours).
>> The message on the screen tells me to look at the System Event Log.
>> Is this just /var/log/messages ?
> 
> The only System Event Log I know of is part of the BIOS.  If you
> enter your BIOS setup you might find something recorded, or you
> can try running "dmidecode -t system" (as root) and see if
> anything meaningful shows up.  There's a manpage for dmidecode,
> but I doubt you'll find much of interest there.

Thanks.
I found as I said in another post that I could read the System Event Log
by pressing F2 on boot.

I see that "dmidecode -t system" does indeed give me
information about the error:
--------------------------------------------------
        Descriptor 2: Single-bit ECC memory error
        Data Format 2: Multiple-event
        Descriptor 3: Multi-bit ECC memory error
        Data Format 3: Multiple-event
--------------------------------------------------

Not as explicit as the System Erro Log , though.
Eg can I tell from this which module is at fault?
(I don't have the faulty module in now.)

Incidentally, does anyone know what the many "Intrusion" entries
in the System Event Log mean?