<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
(	O
Sun	O
4/50	O
,	O
code-named	O
Hobbes	O
)	O
is	O
a	O
workstation	B-Device
that	O
was	O
sold	O
by	O
Sun	O
Microsystems	O
,	O
introduced	O
July	O
1991	O
.	O
</s>
<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
incorporates	O
a	O
40MHz	O
Fujitsu	O
MB86903	O
or	O
Weitek	O
W8701	O
processor	O
.	O
</s>
<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
has	O
four	O
72-pin	O
SIMM	B-General_Concept
slots	O
for	O
memory	O
expansion	O
.	O
</s>
<s>
The	O
memory	O
uses	O
parity	O
Fast	O
Page	O
Memory	O
(	O
FPM	O
)	O
SIMM	B-General_Concept
's	O
with	O
speeds	O
of	O
50-80	O
ns	O
.	O
</s>
<s>
Additional	O
32	O
and	O
64MB	O
SBus	B-Architecture
"	O
Above	O
Board	O
"	O
RAM	O
expanders	O
will	O
fit	O
and	O
work	O
with	O
the	O
IPX	O
using	O
the	O
8-pin	O
J101	O
header	O
which	O
contains	O
additional	O
power	O
and	O
clock	O
signals	O
next	O
to	O
the	O
DMA/Cache	O
controller	O
.	O
</s>
<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
can	O
hold	O
one	O
internal	O
50-pin	O
IDC	O
SCSI	B-Architecture
drive	O
and	O
a	O
floppy	O
drive	O
.	O
</s>
<s>
It	O
also	O
supports	O
external	O
SCSI	B-Architecture
devices	O
.	O
</s>
<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
comes	O
with	O
an	O
on-board	O
AMD	O
Lance	O
Ethernet	O
chipset	O
,	O
which	O
provides	O
an	O
AUI	B-Protocol
connection	O
.	O
</s>
<s>
External	O
AUI	B-Protocol
transceivers	O
are	O
required	O
for	O
connection	O
to	O
10BASE5	O
,	O
10BASE2	O
,	O
10BASE-T	B-Protocol
,	O
or	O
other	O
Ethernet	O
physical	B-Application
layer	I-Application
media	O
.	O
</s>
<s>
Like	O
all	O
other	O
SPARCstation	B-Device
systems	O
,	O
the	O
IPX	O
holds	O
system	O
information	O
such	O
as	O
MAC	O
address	O
and	O
serial	O
number	O
in	O
NVRAM	O
.	O
</s>
<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
includes	O
an	O
integrated	O
Sun	O
Turbo	O
GX	O
cgsix	O
color	O
framebuffer	O
on	O
the	O
internal	O
SBus	B-Architecture
.	O
</s>
<s>
This	O
frees	O
one	O
SBus	B-Architecture
slot	O
from	O
framebuffer	O
duty	O
,	O
which	O
makes	O
the	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
as	O
expandable	O
as	O
the	O
larger	O
form	O
factor	O
SPARCstation	B-Architecture
2	I-Architecture
,	O
with	O
which	O
it	O
otherwise	O
shares	O
many	O
architectural	O
similarities	O
.	O
</s>
<s>
The	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
uses	O
an	O
M48T02	O
battery-backed	O
RTC	O
with	O
RAM	O
chip	O
which	O
handles	O
the	O
real	O
time	O
clock	O
and	O
boot	O
parameter	O
storage	O
.	O
</s>
<s>
The	O
following	O
operating	O
systems	O
will	O
run	O
on	O
a	O
SPARCstation	B-Operating_System
IPX	I-Operating_System
:	O
</s>
<s>
The	O
SPARCstation	B-Architecture
IPC	I-Architecture
(	O
Sun	O
4/40	O
)	O
is	O
an	O
earlier	O
lunchbox	O
form	O
factor	O
system	O
.	O
</s>
<s>
The	O
SPARCstation	B-Architecture
2	I-Architecture
(	O
Sun	O
4/75	O
)	O
is	O
architecturally	O
very	O
similar	O
and	O
can	O
use	O
the	O
same	O
CPU	O
and	O
SBus	B-Architecture
RAM	O
upgrades	O
.	O
</s>
