<s>
Professional	B-Device
Graphics	I-Device
Controller	I-Device
(	O
PGC	O
,	O
often	O
called	O
Professional	B-Device
Graphics	I-Device
Adapter	I-Device
and	O
sometimes	O
Professional	B-Device
Graphics	I-Device
Array	I-Device
)	O
is	O
a	O
graphics	B-Device
card	I-Device
manufactured	O
by	O
IBM	O
for	O
PCs	O
.	O
</s>
<s>
The	O
PGC	O
was	O
,	O
at	O
the	O
time	O
of	O
its	O
release	O
,	O
the	O
most	O
advanced	O
graphics	B-Device
card	I-Device
for	O
the	O
IBM	O
XT	O
and	O
aimed	O
for	O
tasks	O
such	O
as	O
CAD	B-Application
.	O
</s>
<s>
Introduced	O
in	O
1984	O
,	O
the	O
Professional	B-Device
Graphics	I-Device
Controller	I-Device
offered	O
a	O
maximum	O
resolution	O
of	O
640	O
×	O
480	O
with	O
256colors	O
on	O
an	O
analog	O
RGB	O
monitor	O
,	O
at	O
a	O
refresh	O
rate	O
of	O
60hertz	O
—	O
a	O
higher	O
resolution	O
and	O
color	O
depth	O
than	O
CGA	B-Device
and	O
EGA	B-Device
supported	O
.	O
</s>
<s>
This	O
mode	O
is	O
not	O
BIOS-supported	O
.	O
</s>
<s>
It	O
was	O
intended	O
for	O
the	O
computer-aided	B-Application
design	I-Application
market	O
and	O
included	O
320KB	O
of	O
display	O
RAM	B-Architecture
and	O
an	O
on-board	O
Intel	O
8088	B-Device
microprocessor	I-Device
.	O
</s>
<s>
The	O
8088	B-Device
ran	O
software	O
routines	O
such	O
as	O
"	O
draw	O
polygon	O
"	O
and	O
"	O
fill	O
area	O
"	O
from	O
an	O
on-board	O
64KB	O
ROM	B-Device
so	O
that	O
the	O
host	O
CPU	B-General_Concept
did	O
n't	O
need	O
to	O
load	O
and	O
run	O
these	O
routines	O
itself	O
.	O
</s>
<s>
While	O
never	O
widespread	O
in	O
consumer-class	O
personal	O
computers	O
,	O
its	O
list	O
price	O
,	O
plus	O
$	O
1,295	O
display	O
,	O
compared	O
favorably	O
to	O
US$	O
50,000	O
dedicated	O
CAD	B-Application
workstations	I-Application
of	O
the	O
time	O
(	O
even	O
when	O
the	O
$	O
4,995	O
price	O
of	O
a	O
PC	O
XT	O
Model87	O
was	O
included	O
)	O
.	O
</s>
<s>
It	O
was	O
discontinued	O
in	O
1987	O
with	O
the	O
arrival	O
of	O
VGA	B-Protocol
and	O
8514	B-Device
.	O
</s>
<s>
The	O
board	O
was	O
targeted	O
at	O
the	O
CAD	B-Application
market	O
,	O
therefore	O
limited	O
software	O
support	O
is	O
to	O
be	O
expected	O
.	O
</s>
<s>
Color	B-Device
Graphics	I-Device
Adapter	I-Device
text	O
and	O
graphics	O
modes	O
.	O
</s>
<s>
The	O
display	B-Device
adapter	I-Device
was	O
composed	O
of	O
three	O
physical	O
circuit	O
boards	O
(	O
one	O
with	O
the	O
on-board	O
microprocessor	O
,	O
firmware	B-Application
ROMs	O
and	O
video	O
output	O
connector	O
,	O
one	O
providing	O
CGA	B-Device
emulation	O
,	O
and	O
the	O
third	O
mostly	O
carrying	O
RAM	B-Architecture
)	O
and	O
occupied	O
two	O
adjacent	O
expansion	B-Device
slots	I-Device
on	O
the	O
XT	O
or	O
AT	O
motherboard	B-Device
or	O
the	O
Expansion	O
Unit	O
;	O
the	O
third	O
card	O
was	O
located	O
in	O
between	O
the	O
two	O
slots	O
.	O
</s>
<s>
In	O
addition	O
to	O
its	O
native	O
640×480	O
mode	O
,	O
the	O
PGC	O
optionally	O
supported	O
the	O
documented	O
text	O
and	O
graphics	O
modes	O
of	O
the	O
Color	B-Device
Graphics	I-Device
Adapter	I-Device
,	O
which	O
could	O
be	O
enabled	O
using	O
an	O
onboard	O
jumper	O
.	O
</s>
<s>
However	O
,	O
it	O
was	O
only	O
partly	O
register-compatible	O
with	O
CGA	B-Device
.	O
</s>
<s>
The	O
PGC	O
's	O
matching	O
display	O
was	O
the	O
IBM	B-Device
5175	I-Device
,	O
an	O
analog	O
RGB	O
monitor	O
that	O
is	O
unique	O
to	O
it	O
and	O
not	O
compatible	O
with	O
any	O
other	O
video	B-Device
card	I-Device
without	O
modification	O
.	O
</s>
<s>
With	O
hardware	O
modification	O
,	O
the	O
5175	O
can	O
be	O
used	O
with	O
VGA	B-Protocol
,	O
Macintosh	B-Device
,	O
and	O
various	O
other	O
analog	O
RGB	O
video	O
sources	O
.	O
</s>
<s>
Some	O
surplus	O
5175s	O
in	O
VGA-converted	O
form	O
were	O
still	O
sold	O
by	O
catalog	O
retailers	O
such	O
as	O
COMB	O
(	O
Close	O
Out	O
Merchant	O
Buyers	O
)	O
as	O
late	O
as	O
the	O
early	O
1990s	O
.	O
</s>
