<s>
LPX	B-Device
(	O
short	O
for	O
Low	O
Profile	O
eXtension	O
)	O
,	O
originally	O
developed	O
by	O
Western	O
Digital	O
,	O
was	O
a	O
loosely	O
defined	O
motherboard	B-Device
format	O
(	O
form	O
factor	O
)	O
widely	O
used	O
in	O
the	O
1990s	O
.	O
</s>
<s>
There	O
was	O
never	O
any	O
official	O
LPX	B-Device
specification	O
,	O
but	O
the	O
design	O
normally	O
featured	O
a	O
motherboard	B-Device
with	O
the	O
main	O
I/O	O
ports	O
mounted	O
on	O
the	O
back	O
(	O
something	O
that	O
was	O
later	O
adopted	O
by	O
the	O
ATX	B-Language
form	O
factor	O
)	O
,	O
and	O
a	O
riser	B-Architecture
card	I-Architecture
in	O
the	O
center	O
of	O
the	O
motherboard	B-Device
,	O
on	O
which	O
the	O
PCI	B-Protocol
and	O
ISA	B-Architecture
slots	I-Architecture
were	O
mounted	O
.	O
</s>
<s>
Due	O
to	O
the	O
lack	O
of	O
standardized	O
specification	O
,	O
riser	B-Architecture
cards	I-Architecture
were	O
seldom	O
compatible	O
from	O
one	O
motherboard	B-Device
design	O
to	O
another	O
,	O
much	O
less	O
one	O
manufacturer	O
to	O
another	O
.	O
</s>
<s>
The	O
internal	O
PSU	O
connector	O
was	O
of	O
the	O
same	O
type	O
used	O
in	O
the	O
AT	B-Device
form	I-Device
factor	I-Device
.	O
</s>
<s>
One	O
of	O
the	O
more	O
successful	O
features	O
to	O
come	O
out	O
of	O
the	O
LPX	B-Device
specification	O
was	O
its	O
use	O
of	O
more	O
compact	O
power	O
supplies	O
,	O
which	O
later	O
became	O
widely	O
used	O
on	O
Baby	O
AT	O
and	O
even	O
full	O
size	O
AT	O
cases	O
.	O
</s>
<s>
Because	O
LPX	B-Device
form	I-Device
factor	I-Device
power	O
supplies	O
became	O
ubiquitous	O
in	O
most	O
computer	O
cases	O
prior	O
to	O
the	O
ATX	B-Language
standard	O
,	O
it	O
was	O
not	O
unusual	O
for	O
manufacturers	O
to	O
refer	O
to	O
them	O
as	O
"	O
AT	O
"	O
power	O
supplies	O
(	O
or	O
occasionally	O
as	O
"	O
PS/2	B-Device
"	O
power	O
supplies	O
due	O
to	O
its	O
use	O
by	O
the	O
IBM	B-Device
PS/2	I-Device
)	O
,	O
even	O
though	O
the	O
actual	O
AT	O
and	O
Baby	O
AT	O
power	O
supply	O
form	O
factors	O
were	O
larger	O
in	O
size	O
.	O
</s>
<s>
The	O
LPX	B-Device
form	I-Device
factor	I-Device
power	O
supply	O
eventually	O
formed	O
the	O
basis	O
for	O
the	O
ATX	B-Language
form	O
factor	O
power	O
supply	O
,	O
which	O
is	O
the	O
same	O
width	O
and	O
height	O
.	O
</s>
<s>
The	O
specification	O
was	O
very	O
popular	O
in	O
the	O
early-mid	O
1990s	O
,	O
and	O
briefly	O
displaced	O
the	O
AT	B-Device
form	I-Device
factor	I-Device
as	O
the	O
most	O
commonly	O
used	O
.	O
</s>
<s>
However	O
,	O
the	O
release	O
of	O
the	O
Pentium	B-General_Concept
II	I-General_Concept
in	O
1997	O
highlighted	O
the	O
flaws	O
of	O
the	O
format	O
,	O
as	O
a	O
good	O
airflow	O
was	O
important	O
in	O
Pentium	B-General_Concept
II	I-General_Concept
systems	O
,	O
owing	O
to	O
the	O
relatively	O
high	O
heat	O
dispersal	O
requirements	O
of	O
the	O
processor	O
.	O
</s>
<s>
LPX	B-Device
systems	O
suffered	O
a	O
restricted	O
airflow	O
due	O
to	O
the	O
centrally	O
placed	O
riser	B-Architecture
cards	I-Architecture
.	O
</s>
<s>
The	O
introduction	O
of	O
the	O
AGP	B-Architecture
format	O
further	O
complicated	O
matters	O
,	O
as	O
the	O
design	O
not	O
only	O
increased	O
the	O
pin	O
count	O
on	O
riser	B-Architecture
cards	I-Architecture
,	O
but	O
it	O
limited	O
most	O
cards	O
to	O
one	O
AGP	B-Architecture
,	O
one	O
PCI	B-Protocol
and	O
one	O
ISA	B-Architecture
slot	I-Architecture
,	O
which	O
was	O
too	O
restrictive	O
for	O
most	O
users	O
.	O
</s>
<s>
Some	O
lower-quality	O
LPX	B-Device
boards	O
did	O
n't	O
even	O
feature	O
a	O
real	O
AGP	B-Architecture
slot	I-Architecture
,	O
but	O
simply	O
used	O
a	O
physical	O
AGP	B-Architecture
slot	I-Architecture
and	O
connected	O
it	O
to	O
the	O
PCI	B-Protocol
bus	I-Protocol
.	O
</s>
<s>
This	O
was	O
seldom	O
noticed	O
however	O
,	O
as	O
many	O
"	O
AGP	B-Architecture
"	O
graphics	O
cards	O
of	O
the	O
time	O
were	O
in	O
fact	O
PCI	B-Protocol
cards	I-Protocol
internally	O
,	O
and	O
did	O
not	O
take	O
advantage	O
of	O
the	O
features	O
offered	O
by	O
AGP	B-Architecture
.	O
</s>
<s>
LPX	B-Device
was	O
phased	O
out	O
around	O
1998	O
.	O
</s>
<s>
NLX	B-Device
was	O
the	O
intended	O
successor	O
,	O
though	O
many	O
manufacturers	O
chose	O
MicroATX	B-Device
or	O
proprietary	O
motherboard	B-Device
formats	O
instead	O
.	O
</s>
