Acer AL707 Service Manual page 20

III.ALL SCREEN HAS INTERFERENCES OR NOISE, CAN'T BE FIXED BY AUTO KEY
** NOTE: There is so many kind of interferences, 1). One is cause by some VGA-CARD that not meet VESA spec or
power grounding too bad that influence our circuit
2).other is cause by external interferences, move the monitor far from electronic equipment.( rarely
happened)
Use DOT-pattern, or win98/99 shut-down
mode pattern, press "AUTO" key, was the
interferences disappear ??
Adjust "FOCUS" step by step, until the
horizontal interferences disappear
Does your signal-cable have an additional
cable for extension ??
Does your noise only exist in one mode only?
(ex: only at 1280x1024 @ 75 Hz, other is normal)
That was cause by you VGA-CARD setting, your VGA
card timing back porch / front porch exceed vesa timing
too far, for some new AGP-VGA-CARD such situation
always happened
So in your control-panel icon ,select monitor ,setting ,
advance ,screen-adjust ,at
Size icon, increase step by step slowly, press ""AUTO"
key every step you increase the SIZE . repeat the
procedure( increase/decrease SIZE one-step and press
AUTO) until the interferences disappear, press "APPLY"
to save in your VGA
NG, interferences still exist
NG
Yes, has extension
NO additional extension
Yes, only happened on one mode
OK
END
OK
END
Put away the additional cable
May be the additional cable grounding is
not quite well
cable
NO, all mode
Change the Signal-cable to new-one or
Try other brand VGA-CARD
(make sure just only that brand VGA-
CARD has this problem ,contact RD-
Taipei)
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