Hey everyone! First post! 
I have a Samsung LED LCD monitor that someone else had given up on (SyncMaster SA300 LS24A300BS, the last two letters seem to specify the build quality...). The problem with the monitor is that when no VGA/DVI cable is connected, it seems to work fine - backlighting glows, and the standard "no signal" message is shown on the screen, forever, so there seems to be no problem with the panel itself as far as I can tell.
As soon as I plug in a DVI or VGA cable, the screen goes black (no backlighting). With DVI it just goes black but power indicator keeps shining, with VGA the indicator starts flashing on and off to indicate some error until I "restart" the monitor. I've been trying to check for video by looking closely (to see if it's only the backlighting that stops) but can't see anything but black.
The screen goes black before any actual video is displayed, but not instantly when plugging in the cable either. I guess the delay before it goes black is about the same as the delay from a cable is inserted to actual video is displayed on the screen on a working monitor.
The main board is VERY similar to this one: http://www.shopjimmy.com/samsung-bn9...4a300bs-za.htm (it's not exactly the same, but it has the exact same layout that and that board is supposed to be compatible with mine and I can't see any difference except brands of the components)
By my awesome power of deduction, I have concluded that something is broken on the main board. The mainboard takes DC 14V (from an external PSU), VGA and DVI, and is connected internally to the another board attached to the panel itself (disconnecting this board completely makes the screen go bright white, but it still goes black when a cable is attached), the backlighting (seems to be powered directly from the mainboard, no inverter board or whatever as far as I can tell), and to the panel of buttons on the edge of the screen.
I'm trying to find a replacement board (that with shipping to EU is not more than half of what the monitor cost new) but seems to be out of luck, also I have nothing to lose by at least trying to repair the board I have. I do however suck at this. Any idea what might be wrong with the board? There is no visible damage to the board (no leaking caps etc). The standard thing to do on broken LCD monitors seems to be to replace the caps, but there are only 4 caps in the entire monitor and I'm not sure if broken caps could cause this behaviour? I'm just assuming that the VERY tiny 24W PSU is alright, as the screen works alright forever when displaying the "no signal" screen.
Any help is appreciated!
EDIT: Also, the computers detect the monitor on both VGA and DVI and they think the monitor is connected and working well.
I have a Samsung LED LCD monitor that someone else had given up on (SyncMaster SA300 LS24A300BS, the last two letters seem to specify the build quality...). The problem with the monitor is that when no VGA/DVI cable is connected, it seems to work fine - backlighting glows, and the standard "no signal" message is shown on the screen, forever, so there seems to be no problem with the panel itself as far as I can tell.
As soon as I plug in a DVI or VGA cable, the screen goes black (no backlighting). With DVI it just goes black but power indicator keeps shining, with VGA the indicator starts flashing on and off to indicate some error until I "restart" the monitor. I've been trying to check for video by looking closely (to see if it's only the backlighting that stops) but can't see anything but black.
The screen goes black before any actual video is displayed, but not instantly when plugging in the cable either. I guess the delay before it goes black is about the same as the delay from a cable is inserted to actual video is displayed on the screen on a working monitor.
The main board is VERY similar to this one: http://www.shopjimmy.com/samsung-bn9...4a300bs-za.htm (it's not exactly the same, but it has the exact same layout that and that board is supposed to be compatible with mine and I can't see any difference except brands of the components)
By my awesome power of deduction, I have concluded that something is broken on the main board. The mainboard takes DC 14V (from an external PSU), VGA and DVI, and is connected internally to the another board attached to the panel itself (disconnecting this board completely makes the screen go bright white, but it still goes black when a cable is attached), the backlighting (seems to be powered directly from the mainboard, no inverter board or whatever as far as I can tell), and to the panel of buttons on the edge of the screen.
I'm trying to find a replacement board (that with shipping to EU is not more than half of what the monitor cost new) but seems to be out of luck, also I have nothing to lose by at least trying to repair the board I have. I do however suck at this. Any idea what might be wrong with the board? There is no visible damage to the board (no leaking caps etc). The standard thing to do on broken LCD monitors seems to be to replace the caps, but there are only 4 caps in the entire monitor and I'm not sure if broken caps could cause this behaviour? I'm just assuming that the VERY tiny 24W PSU is alright, as the screen works alright forever when displaying the "no signal" screen.
Any help is appreciated!
EDIT: Also, the computers detect the monitor on both VGA and DVI and they think the monitor is connected and working well.
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