Re: Thinkpad R31 LCD problem; starts dark, then brightens

In news:dd5ec$4866c7a7$7822@xxxxxxxxxxxxxxxxx,
Barry Watzman typed on Sat, 28 Jun 2008 19:22:03 -0400:
I doubt it's a loose connection, that would probably kill the lamp
totally.

Me too. But it could be a loose solder connection on the inverter or the lamp itself which could act like a loose connection too.

It's not video card (which in most cases IS [on] the motherboard) to
the LCD panel.

True.

There is wiring from the laptop base to the inverter (note: the
inverter, not the LCD panel), and there are two (2) wires from the
inverter to the lamp (which is physically located inside of the LCD
panel, but which is really not a "part" of the panel, per se). The
wiring from the base to the inverter is usually just a few wires (3 to
6) and they are usually individual wires not a fancy "flex" or other.
highly custom cable.

True.

The two wires to the lamp are unique in that
they are silver wire, and at least one of them is usually heavily
insulated as they (or at least one of them) carry(s) high voltage (hundreds of volts to possibly well over 1,000 volts).

1800 volts. I have seen other colors besides silver. White for one.

ken10254 wrote:
On Jun 28, 3:00 pm, "BillW50" <Bill...@xxxxxxx> wrote:
Innews:4a544$486693d1$18470@xxxxxxxxxxxxxxxxx,
Barry Watzman typed on Sat, 28 Jun 2008 15:40:53 -0400:



I think it's a software issue. First, lcd panels use fluorescent
tubes for backlights, and it is normal for them to take up to 1-2
minutes to reach full brightness (this gets much worse with very
old lamps). But your comment that you can hit the function key to
get the brightness up suggests that it's not a hardware issue at
all, but rather a (software) configuration issue.
ken10254 wrote:
I took this laptop in on trade. It's a Thinkpad R31 2656 M2U;
Celeron 1.2, 14.1"LCD at 1024 x 768.
XP Pro. When it boots up the screen is very dark; Windows splash
screen is hardly visible, but on an external LCD everything looks
fine. Once into XP, I can hit the function key/brightness control
combo keys a few times and usually get the screen to come back on.
The external LCD works fine at all times, so I am assuming the
video card is fine. Can anyone help me figure out if this an
inverter problem, or something else? Would a loose connection
cause this? Any suggestions would be greatly appreciated. Thanks!
** Posted fromhttp://www.teranews.com**
Lamps will get dimmer and dimmer with age. So the dim display to me
sounds like an aged lamp. Although the OP and fabianusv say it also
acts like a loose connection. This could be the lamp and/or the
inverter. --
Bill
Gateway Celeron M 370 (1.5GHZ)
MX6124 (laptop) w/1GB
Windows XP Home SP2 (60GB HD)
Intel(r) 910GML (64MB shared)

Bill;
If this is caused by a loose connection, which connection would that
be? Video card to motherboard? Inverter to lamps? Any suggestions?
Thanks!
** Posted from http://www.teranews.com **

--
Bill
Gateway Celeron M 370 (1.5GHZ)
MX6124 (laptop) w/1GB
Windows XP Home SP2 (60GB HD)
Intel(r) 910GML (64MB shared)

.

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