Hardware Reference
In-Depth Information
custom power supplies made that duplicated the nonstandard pinout of the motherboard
power connectors.
An even bigger crime than simply using nonstandard power connectors is that only the
pinout is nonstandard; the connectors look like and are keyed the same as is dictated by
true ATX. Therefore, nothing prevents you from plugging one of these Dell nonstandard
power supplies into a new industry-standard ATX motherboard you installed in the Dell
case as an upgrade, or even plugging a new upgraded industry-standard ATX power sup-
ply into the existing Dell motherboard. But mixing either a new ATX board with the non-
standard Dell supply or a new ATX supply with the non-standard Dell motherboard is a
recipe for silicon toast.
Tables 18.17
and
18.18
show the nonstandard Dell main and auxiliary power supply con-
nections. This nonstandard wiring is used on some of Dell's early pseudo-ATX systems.
Table 18.17 Dell Proprietary (Nonstandard) 20-Pin ATX Main Power Connector Pinout (Wire End
View)
Table 18.18 Dell Proprietary (Nonstandard) ATX Auxiliary Power Connector Pinout
If you study the Dell main and auxiliary connector pinouts I've listed here and compare
them to the industry-standard ATX pinouts listed earlier, you'll see that not only are
the voltage and signal positions changed, but the number of terminals carrying specific
voltages and grounds has changed as well. You could possibly modify a Dell supply to
work with a standard ATX board or modify a standard ATX supply to work with a Dell
