<s>
Generalized	B-General_Concept
Timing	I-General_Concept
Formula	I-General_Concept
is	O
a	O
standard	O
by	O
VESA	O
which	O
defines	O
exact	O
parameters	O
of	O
the	O
component	O
video	O
signal	O
for	O
analogue	O
VGA	B-Protocol
display	O
interface	O
.	O
</s>
<s>
The	O
video	O
parameters	O
defined	O
by	O
the	O
standard	O
include	O
horizontal	B-General_Concept
blanking	O
(	O
retrace	O
)	O
and	O
vertical	O
blanking	O
intervals	O
,	O
horizontal	B-General_Concept
frequency	I-General_Concept
and	O
vertical	O
frequency	O
(	O
collectively	O
,	O
pixel	O
clock	O
rate	O
or	O
video	O
signal	B-Algorithm
bandwidth	I-Algorithm
)	O
,	O
and	O
horizontal/vertical	O
sync	O
polarity	O
.	O
</s>
<s>
At	O
the	O
same	O
time	O
,	O
a	O
compliant	O
graphics	O
card	O
is	O
expected	O
to	O
use	O
the	O
calculation	O
to	O
produce	O
a	O
signal	O
that	O
will	O
work	O
on	O
the	O
display	O
—	O
either	O
a	O
GTF	O
default	O
formula	O
for	O
then-ordinary	O
CRT	O
displays	O
or	O
via	O
a	O
custom	O
formula	O
provided	O
via	O
EDID	B-General_Concept
signaling	O
.	O
</s>
<s>
These	O
parameters	O
are	O
used	O
by	O
the	O
XFree86	B-Device
Modeline	I-Device
,	O
for	O
example	O
.	O
</s>
<s>
The	O
standard	O
was	O
adopted	O
in	O
1999	O
,	O
and	O
was	O
superseded	O
by	O
the	O
Coordinated	B-General_Concept
Video	I-General_Concept
Timings	I-General_Concept
specification	O
in	O
2002	O
.	O
</s>
