<s>
SGI	B-Device
Visual	I-Device
Workstation	I-Device
is	O
a	O
series	O
of	O
workstation	B-Device
computers	I-Device
that	O
are	O
designed	O
and	O
manufactured	O
by	O
SGI	O
.	O
</s>
<s>
Unlike	O
its	O
other	O
product	O
lines	O
,	O
which	O
used	O
the	O
64-bit	O
MIPS	B-Device
RISC	B-Architecture
architecture	O
,	O
the	O
line	O
used	O
Intel	B-General_Concept
Pentium	I-General_Concept
II	I-General_Concept
and	O
III	B-General_Concept
processors	O
and	O
shipped	O
with	O
Windows	B-Device
NT	I-Device
4.0	I-Device
or	O
Windows	B-Application
2000	I-Application
as	O
its	O
operating	O
system	O
in	O
lieu	O
of	O
IRIX	B-Operating_System
.	O
</s>
<s>
However	O
,	O
the	O
Visual	B-Device
Workstation	I-Device
320	O
and	O
540	O
models	O
deviated	O
from	O
the	O
architecture	O
of	O
IBM-compatible	O
PCs	B-Device
by	O
using	O
SGI	O
's	O
ARCS	B-Device
firmware	B-Application
instead	O
of	O
a	O
traditional	O
BIOS	B-Operating_System
,	O
internal	O
components	O
adapted	O
from	O
its	O
MIPS-based	O
products	O
,	O
and	O
other	O
proprietary	O
components	O
that	O
made	O
them	O
incompatible	O
with	O
internal	O
hardware	O
designed	O
for	O
standard	O
PCs	B-Device
and	O
hence	O
unable	O
to	O
run	O
other	O
versions	O
of	O
Microsoft	B-Application
Windows	I-Application
,	O
especially	O
Windows	O
9x	O
.	O
</s>
<s>
By	O
contrast	O
,	O
the	O
remaining	O
models	O
in	O
the	O
line	O
are	O
standard	O
PCs	B-Device
,	O
using	O
VIA	O
Technologies	O
chipsets	O
,	O
Nvidia	O
video	O
cards	O
,	O
and	O
standard	O
components	O
.	O
</s>
<s>
There	O
are	O
two	O
series	O
of	O
the	O
Visual	B-Device
Workstations	I-Device
.	O
</s>
<s>
All	O
are	O
based	O
on	O
Intel	O
processors	O
;	O
the	O
first	O
series	O
(	O
320	O
and	O
540	O
)	O
used	O
SGI	O
's	O
ARCloader	O
PROM	O
and	O
Cobalt	O
video	O
chipset	O
,	O
the	O
remainder	O
are	O
essentially	O
standard	O
PCs	B-Device
.	O
</s>
<s>
The	O
firmware	B-Application
used	O
in	O
these	O
systems	O
is	O
a	O
PROM	O
that	O
enables	O
booting	O
into	O
a	O
graphical	O
subsystem	O
before	O
the	O
OS	O
was	O
loaded	O
.	O
</s>
<s>
In	O
this	O
regard	O
they	O
resemble	O
the	O
Irix/MIPS	O
line	O
of	O
SGI	O
computers	O
such	O
as	O
the	O
SGI	B-Device
O2	I-Device
.	O
</s>
<s>
The	O
320	O
and	O
540	O
also	O
stand	O
out	O
for	O
having	O
FireWire	B-Protocol
(	O
IEEE	B-Protocol
1394	I-Protocol
)	O
ports	O
,	O
onboard	O
composite/S	O
-video	O
capture	O
,	O
and	O
USB	O
keyboards	O
and	O
mice	O
.	O
</s>
<s>
They	O
differ	O
from	O
each	O
other	O
in	O
that	O
the	O
320	O
is	O
dual	O
Pentium	O
II/III	O
-capable	O
with	O
1GB	O
maximum	O
system	O
RAM	O
,	O
while	O
the	O
540	O
is	O
quad	O
Pentium	B-General_Concept
III	I-General_Concept
Xeon-capable	O
with	O
2GB	O
maximum	O
system	O
RAM	O
.	O
</s>
<s>
Both	O
computers	O
use	O
a	O
proprietary	O
DIMM	O
module	O
that	O
is	O
essentially	O
the	O
same	O
as	O
ECC	O
SDRAM	O
PC-100	O
,	O
but	O
in	O
a	O
package	O
one-half	O
normal	O
size	O
.	O
</s>
<s>
The	O
FireWire	B-Protocol
ports	I-Protocol
that	O
are	O
built	O
into	O
the	O
320	O
never	O
functioned	O
.	O
</s>
<s>
SGI	O
distributed	O
Orange	O
Micro	O
FireWire	B-Protocol
cards	O
about	O
a	O
year	O
after	O
production	O
commenced	O
,	O
in	O
lieu	O
of	O
fixing	O
the	O
FireWire	B-Protocol
ports	I-Protocol
.	O
</s>
<s>
The	O
other	O
Visual	B-Device
Workstations	I-Device
are	O
built	O
to	O
compete	O
with	O
the	O
new	O
Intel	O
processor	O
based	O
workstations	B-Device
that	O
are	O
considerably	O
cheaper	O
than	O
SGI	O
's	O
line	O
of	O
MIPS	B-Device
workstations	B-Device
.	O
</s>
<s>
They	O
are	O
little	O
more	O
than	O
standard	O
PCs	B-Device
,	O
and	O
use	O
many	O
parts	O
that	O
are	O
also	O
available	O
in	O
the	O
aftermarket	O
.	O
</s>
<s>
The	O
320	O
and	O
540	O
Visual	B-Device
Workstations	I-Device
shipped	O
originally	O
with	O
Microsoft	B-Device
Windows	I-Device
NT	I-Device
4.0	I-Device
.	O
</s>
<s>
Due	O
to	O
the	O
ARCloader	O
PROM	O
,	O
a	O
custom	O
Hardware	B-Operating_System
Abstraction	I-Operating_System
Layer	I-Operating_System
(	O
HAL	O
)	O
for	O
Windows	O
is	O
necessary	O
.	O
</s>
<s>
Windows	B-Application
2000	I-Application
is	O
the	O
last	O
release	O
which	O
included	O
the	O
required	O
SGI-specific	O
HAL	O
.	O
</s>
<s>
Because	O
of	O
that	O
,	O
and	O
because	O
SGI	O
ceased	O
supporting	O
the	O
Visual	B-Device
Workstation	I-Device
series	O
,	O
installation	O
of	O
later	O
Windows	O
versions	O
such	O
as	O
XP	O
is	O
unsupported	O
.	O
</s>
<s>
Because	O
of	O
the	O
various	O
SGI	O
enhancements	O
,	O
in	O
particular	O
for	O
the	O
320	O
and	O
540	O
,	O
Visual	B-Device
Workstations	I-Device
often	O
out-perform	O
Intel	O
PCs	B-Device
of	O
similar	O
configuration	O
in	O
graphically-intensive	O
or	O
memory	B-General_Concept
bound	I-General_Concept
applications	O
.	O
</s>
<s>
However	O
,	O
due	O
to	O
the	O
hefty	O
upgrade	O
costs	O
for	O
the	O
non-standard	O
components	O
,	O
it	O
was	O
more	O
cost	O
effective	O
to	O
purchase	O
an	O
entire	O
new	O
higher-spec	O
non-SGI	O
PC	B-Device
rather	O
than	O
purchase	O
upgrades	O
to	O
a	O
Visual	B-Device
Workstation	I-Device
.	O
</s>
<s>
All	O
the	O
Visual	B-Device
Workstations	I-Device
support	O
conventional	O
CRT	O
monitors	O
and	O
have	O
VGA	O
display	O
connectors	O
.	O
</s>
<s>
The	O
SGI	O
320	O
and	O
540	O
models	O
shipped	O
with	O
the	O
groundbreaking	O
and	O
stylistically	O
matched	O
1600SW	B-Device
LCD	O
display	O
,	O
using	O
an	O
OpenLDI	B-Protocol
display	O
connector	O
that	O
requires	O
an	O
accessory	O
flat	O
panel	O
adapter	O
.	O
</s>
<s>
The	O
SGI	B-Device
O2	I-Device
also	O
supports	O
the	O
1600SW	B-Device
with	O
an	O
adapter	O
.	O
</s>
<s>
The	O
model	O
numbers	O
of	O
the	O
Visual	B-Device
Workstations	I-Device
:	O
</s>
<s>
Visual	B-Device
Workstations	I-Device
were	O
initially	O
equipped	O
with	O
either	O
a	O
single	O
Pentium	B-General_Concept
II	I-General_Concept
or	O
Pentium	B-General_Concept
III	I-General_Concept
processor	O
or	O
dual	O
(	O
SMP	B-Operating_System
)	O
Pentium	B-General_Concept
III	I-General_Concept
processors	O
.	O
</s>
<s>
The	O
540	O
and	O
550	O
models	O
support	O
the	O
Xeon	B-Device
implementation	O
of	O
the	O
Pentium	O
series	O
,	O
and	O
could	O
support	O
up	O
to	O
four	O
Xeons	B-Device
in	O
an	O
SMP	B-Operating_System
configuration	O
(	O
only	O
two	O
for	O
the	O
550	O
)	O
.	O
</s>
<s>
Although	O
no	O
SGI	B-Device
Visual	I-Device
Workstation	I-Device
was	O
ever	O
released	O
with	O
a	O
CPU	O
running	O
higher	O
than	O
700MHz	O
,	O
some	O
hobbyists	O
have	O
been	O
able	O
to	O
run	O
faster	O
processors	O
.	O
</s>
<s>
For	O
the	O
SGI	O
320	O
,	O
the	O
limit	O
is	O
dual	O
1	O
GHz	O
Pentium	B-General_Concept
III	I-General_Concept
processors	O
or	O
a	O
single	O
1.4GHz	O
Celeron	O
.	O
</s>
<s>
With	O
single	O
processors	O
the	O
Powerleap	O
Pl-iP3T	O
"	O
slocket	B-General_Concept
"	O
adapter	O
and	O
a	O
Tualatin	O
1.4GHz	O
Celeron	O
processor	O
is	O
the	O
limit	O
,	O
and	O
is	O
a	O
straight	O
bolt-in	O
installation	O
.	O
</s>
<s>
The	O
SGI	O
540	O
has	O
been	O
reported	O
to	O
handle	O
up	O
to	O
900MHz	O
quad	O
Xeon	B-Device
processors	O
.	O
</s>
<s>
These	O
are	O
the	O
fastest	O
Pentium	B-General_Concept
III	I-General_Concept
Xeons	B-Device
with	O
the	O
100MHz	O
front	O
side	O
bus	O
speed	O
of	O
the	O
540	O
.	O
</s>
<s>
The	O
230	O
,	O
330	O
,	O
and	O
550	O
models	O
are	O
essentially	O
standard	O
PCs	B-Device
and	O
has	O
the	O
same	O
capabilities	O
and	O
upgrade	O
limits	O
as	O
other	O
PCs	B-Device
of	O
the	O
time	O
.	O
</s>
<s>
The	O
230	O
and	O
330	O
are	O
based	O
on	O
VIA	O
chipsets	O
,	O
used	O
socket	B-Device
370	I-Device
processors	O
,	O
and	O
conventional	O
SDRAM	O
.	O
</s>
<s>
The	O
550	O
used	O
Slot	B-Device
2	I-Device
Xeon	B-Device
processors	O
,	O
the	O
Intel	B-Device
840	I-Device
chipset	O
,	O
and	O
RDRAM	O
.	O
</s>
