<s>
Sun-4	B-Device
is	O
a	O
series	O
of	O
Unix	B-Device
workstations	I-Device
and	O
servers	O
produced	O
by	O
Sun	O
Microsystems	O
,	O
launched	O
in	O
1987	O
.	O
</s>
<s>
The	O
original	O
Sun-4	B-Device
series	O
were	O
VMEbus-based	O
systems	O
similar	O
to	O
the	O
earlier	O
Sun-3	B-Device
series	O
,	O
but	O
employing	O
microprocessors	B-Architecture
based	O
on	O
Sun	O
's	O
own	O
SPARC	B-Architecture
V7	I-Architecture
RISC	B-Architecture
architecture	O
in	O
place	O
of	O
the	O
68k	B-Device
family	O
processors	O
of	O
previous	O
Sun	O
models	O
.	O
</s>
<s>
Sun	B-Device
4/280	I-Device
was	O
known	O
as	O
base	O
system	O
that	O
was	O
used	O
for	O
building	O
of	O
first	O
RAID	B-Architecture
prototype	O
.	O
</s>
<s>
In	O
1989	O
,	O
Sun	O
dropped	O
the	O
"	O
Sun-4	B-Device
"	O
name	O
for	O
marketing	O
purposes	O
in	O
favor	O
of	O
the	O
SPARCstation	B-Device
and	O
SPARCserver	B-Device
brands	O
for	O
new	O
models	O
,	O
although	O
early	O
SPARCstation/server	O
models	O
were	O
also	O
assigned	O
Sun-4-series	O
model	O
numbers	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
SPARCstation	B-Architecture
1	I-Architecture
was	O
also	O
known	O
as	O
the	O
Sun	O
4/60	O
.	O
</s>
<s>
This	O
practice	O
was	O
phased	O
out	O
with	O
the	O
introduction	O
of	O
the	O
SPARCserver	B-Device
600MP	O
series	O
in	O
1991	O
.	O
</s>
<s>
The	O
term	O
Sun-4	B-Device
continued	O
to	O
be	O
used	O
in	O
an	O
engineering	O
context	O
to	O
identify	O
the	O
basic	O
hardware	O
architecture	O
of	O
all	O
SPARC-based	O
Sun	O
systems	O
.	O
</s>
<s>
Sun	O
4/110	O
,	O
4/150	O
,	O
4/260	O
and	O
4/280	O
systems	O
upgraded	O
with	O
the	O
Sun	O
4300	O
CPU	O
board	O
(	O
as	O
used	O
in	O
the	O
SPARCserver	B-Device
300	O
series	O
)	O
were	O
referred	O
to	O
as	O
the	O
4/310	O
,	O
4/350	O
,	O
4/360	O
and	O
4/380	O
respectively	O
.	O
</s>
<s>
The	O
Sun-4	B-Device
architecture	O
refers	O
to	O
the	O
VME-based	O
architecture	O
described	O
above	O
and	O
used	O
in	O
the	O
Sun	O
4/100	O
,	O
4/200	O
,	O
SPARCserver	B-Device
300	O
and	O
SPARCserver	B-Device
400	O
ranges	O
.	O
</s>
<s>
Sun-4	B-Device
support	O
was	O
included	O
in	O
SunOS	B-Operating_System
3.2	O
onwards	O
and	O
Solaris	B-Application
2.1	O
to	O
2.4	O
.	O
</s>
<s>
OpenBSD	B-Operating_System
and	O
NetBSD	B-Device
also	O
will	O
run	O
on	O
the	O
Sun-4	B-Device
architecture	O
families	O
.	O
</s>
<s>
Several	O
variations	O
on	O
the	O
Sun-4	B-Device
architecture	O
were	O
subsequently	O
developed	O
and	O
used	O
in	O
later	O
computer	O
systems	O
produced	O
by	O
Sun	O
and	O
other	O
vendors	O
.	O
</s>
<s>
Sun-4c	B-Device
(	O
C	O
presumably	O
for	O
Campus	O
,	O
the	O
codename	O
of	O
the	O
first	O
Sun-4c	B-Device
model	O
,	O
the	O
SPARCstation	B-Architecture
1	I-Architecture
)	O
This	O
desktop	O
workstation/low	O
-end	O
server	B-Application
variant	O
substituted	O
the	O
32-bit	O
SBus	B-Architecture
expansion	O
bus	O
in	O
place	O
of	O
VME	O
and	O
introduced	O
a	O
new	O
MMU	O
design	O
.	O
</s>
<s>
Supported	O
by	O
SunOS	B-Operating_System
4.0.3c	O
onwards	O
and	O
Solaris	B-Application
2.0	O
to	O
7	O
.	O
</s>
<s>
Sun-4e	O
A	O
hybrid	O
Sun-4c/VME	O
architecture	O
found	O
in	O
the	O
SPARCengine	O
1	O
(	O
Sun	O
4/E	O
)	O
VME	O
embedded	O
controller	O
.	O
</s>
<s>
Supported	O
by	O
SunOS	B-Operating_System
4.0.3e	O
and	O
4.1e	O
and	O
Solaris	B-Application
2.1	O
to	O
2.4	O
.	O
</s>
<s>
Sun-4m	O
Originally	O
a	O
multiprocessor	B-Operating_System
Sun-4	B-Device
variant	O
,	O
based	O
on	O
the	O
MBus	B-Architecture
processor	O
module	O
bus	O
introduced	O
in	O
the	O
SPARCserver	B-Device
600MP	O
series	O
.	O
</s>
<s>
The	O
Sun-4m	O
architecture	O
later	O
also	O
encompassed	O
non-MBus	O
uniprocessor	O
systems	O
such	O
as	O
the	O
SPARCstation	B-Architecture
5	I-Architecture
,	O
utilizing	O
SPARC	O
V8-architecture	O
processors	O
.	O
</s>
<s>
Supported	O
by	O
SunOS	O
4.1.2	O
onwards	O
and	O
Solaris	B-Application
2.1	O
to	O
9	O
.	O
</s>
<s>
SPARCserver	B-Device
600MP	O
support	O
was	O
dropped	O
after	O
Solaris	O
2.5.1	O
.	O
</s>
<s>
Sun-4d	B-Device
(	O
D	O
for	O
Dragon	O
,	O
the	O
codename	O
of	O
the	O
SPARCcenter	B-Device
2000	O
)	O
A	O
high-end	O
multiprocessor	B-Operating_System
architecture	O
,	O
based	O
on	O
the	O
XDBus	O
processor	O
interconnect	O
,	O
scalable	O
up	O
to	O
20	O
processors	O
.	O
</s>
<s>
The	O
only	O
Sun-4d	B-Device
systems	O
produced	O
by	O
Sun	O
were	O
the	O
SPARCserver	B-Device
1000	O
and	O
SPARCcenter	B-Device
2000	O
series	O
.	O
</s>
<s>
The	O
Cray	B-Device
CS6400	I-Device
was	O
also	O
nominally	O
a	O
Sun-4d	B-Device
machine	O
(	O
sun4d6	O
)	O
,	O
although	O
it	O
required	O
a	O
custom	O
version	O
of	O
Solaris	B-Application
.	O
</s>
<s>
Supported	O
by	O
Solaris	B-Application
2.2	O
to	O
8	O
.	O
</s>
<s>
Sun-4u	B-Device
(	O
U	O
for	O
UltraSPARC	B-General_Concept
)	O
-	O
this	O
variant	O
introduced	O
the	O
64-bit	B-Device
SPARC	B-Architecture
V9	I-Architecture
processor	O
architecture	O
and	O
UPA	O
processor	O
interconnect	O
first	O
used	O
in	O
the	O
Sun	B-Device
Ultra	I-Device
series	I-Device
.	O
</s>
<s>
Supported	O
by	O
32-bit	O
versions	O
of	O
Solaris	B-Application
from	O
the	O
version	O
2.5	O
.	O
</s>
<s>
The	O
first	O
64-bit	B-Device
Solaris	B-Application
release	O
for	O
Sun4u	O
is	O
Solaris	B-Application
7	I-Application
.	O
</s>
<s>
UltraSPARC	B-General_Concept
I	O
support	O
was	O
dropped	O
after	O
Solaris	B-Application
9	I-Application
.	O
</s>
<s>
Solaris	B-Application
10	I-Application
supports	O
Sun4u	O
implementations	O
from	O
UltraSPARC	B-General_Concept
II	I-General_Concept
to	O
UltraSPARC	B-General_Concept
IV	I-General_Concept
.	O
</s>
<s>
Sun-4u1	O
Sometimes	O
used	O
to	O
identify	O
the	O
Sun	B-Device
Enterprise	I-Device
10000	I-Device
(	O
Starfire	O
)	O
64-way	O
multiprocessor	B-Operating_System
server	B-Application
architecture	O
.	O
</s>
<s>
Sun-4us	B-Device
A	O
variant	O
of	O
Sun-4u	B-Device
specific	O
to	O
Fujitsu	O
PRIMEPOWER	O
systems	O
based	O
on	O
SPARC64	B-Device
V	I-Device
processors	O
.	O
</s>
<s>
Sun-4v	B-Device
(	O
V	O
presumably	O
for	O
"	O
virtualized	O
"	O
)	O
A	O
variation	O
on	O
Sun-4u	B-Device
which	O
includes	O
hypervisor	B-Operating_System
processor	O
virtualization	O
;	O
introduced	O
in	O
the	O
UltraSPARC	B-General_Concept
T1	I-General_Concept
(	O
Niagara	B-General_Concept
)	O
multicore	B-Architecture
processor	I-Architecture
.	O
</s>
<s>
Supported	O
by	O
Solaris	B-Application
version	O
10	O
starting	O
from	O
release	O
3/05	O
HW2	O
,	O
and	O
Solaris	B-Application
11	I-Application
.	O
</s>
