John wrote:

> On the systems I have to work with [...]

I didn't specify what they were.

CPU: Intel Pentium 3

# cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 11
model name      : Intel(R) Pentium(R) III CPU - S         1266MHz
stepping        : 4
cpu MHz         : 1266.700
cache size      : 512 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca 
cmov pat pse36 mmx fxsr sse
bogomips        : 2533.40
clflush size    : 32

Motherboard: Adlink EBC-2000T
http://www.adlinktech.com/PD/web/PD_detail.php?pid=213

Chipset: VIA Pro133T
http://www.via.com.tw/en/products/chipsets/legacy/pro133/
VT82C694T north bridge + VT82C686B south bridge

AFAIU, the south bridge can be a source of SMIs.
Can the north bridge also be a source of SMIs?

What I/O ports do I need to write to, and what values should I write to 
these ports, in order to prevent the VT82C686B from sending SMIs?

Regards.