View Full Version : Blank screen

11-19-2007, 12:14 AM
Went to clean the dust blocking the heatsink and fan in my Dell Inspiron 1100 laptop today. #Got everything out and put back together. #When I try to power the computer up, the screen stays blank and the activity light stays out. #I'm thinking the motherboard is toast. #What are the expert opinions here?

edit: #The fan turns on and the power light comes on. That's all.

11-19-2007, 12:23 AM
No fans, no HD activity, nothing?
Check the power supply connections to the mobo. You may have knocked something loose while cleaning.

If you've got fans and LED's hook up an outboard monitor to check the video subsystem.

11-19-2007, 02:08 AM
That will teach you to keep things clean. I'm agin it--

Tom K8ERV Montrose Co.

11-19-2007, 06:38 AM
Well, I haven't done anything with any Dell laptops but have taken apart a Toshiba, Sony, and HP. They all have a bunch of little connectors that can be easily knocked out. Best bet is to open it up again and check to make sure some little connector or ribbon cable didn't pull loose. I know, I've done it. It's a real pain to put the whole thing together and then have to take out 100 screws again because you forgot to plug something back in.

11-20-2007, 10:54 PM
I'll try taking it apart again to look for loose connections. Hopefully that is all that's wrong!

11-20-2007, 11:10 PM
Does that machine have an exterior VGA connector? You might try connecting it to an external monitor and trying to boot it.

11-21-2007, 06:26 AM
You probably knocked a cable or power connector loose or something like that. It doesn't take much! Could be a loosened card in a slot too.

11-22-2007, 03:43 AM
There's a ribbon cable that slides into the socket on the MoBo, gently grip it by the sides and slide it back into the socket, that happens to my Compaq Notebook all the time... http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif Be gentle and it will fire up for you.

Keep us posted! http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif


11-22-2007, 08:00 PM
Checked, double checked, triple checked. Still no solution. I don't have an external monitor available at the moment so I can't check that, but there is no activity at all in the computer so it's probably not the screen.

11-22-2007, 10:25 PM
How did you go about cleaning it? Compressed air, blowing on it, garden hose? (just kidding, but I did get some looks when I cleaned my work keyboard by dunking it in the sink. You can do that as long as it is completely dry when you plug it back in)

There was a problem with some Toshiba laptops a while back where the video chip would work it's way loose from the mainboard. If you pushed down on the right spot on the case it would re-seat itself.

Possibly there is a similar problem with yours? Though most manufacturers put some epoxy on them to keep em put. I had a Toshiba's video chip fail and unfortunately they started putting epoxy to hold them tight so I couldn't even remove it without causing damage.

It's just weird that you get no activity at all. Whenever I see that (turn power on and everything just locks up) it has usually been a cable/component not plugged in correctly or a master/slave misconfiguration. It's possible you fried something but it doesn't seem likely unless you did some pretty aggressive cleaning in there.

11-23-2007, 01:26 AM
Did you happen to give any of the cooling fans a good spin with the compressed air? I blew the diodes in a power supply (desktop machine) by doing this. A DC fan, when spun fast enough without any current applied becomes a DC generator.

I stick pencils or toothpicks in all fans now before I break out the air compressor. I hope this isn't the case on your laptop ... you may have blown any protection diodes on the MB for the fan circuit (if it even has any!).

Good luck!

12-13-2007, 12:32 PM
the last time that situation happened to me it was a bad video card - but since the video card is not a plugin and is part of the motherboard, it effects other things (like hard drive activity and such) dell needed to replace the motherboard.