No lcd video on laptop but works fine on an external monitor

[capopp]

I just replaced a system board and double-checked to make sure everthing is plugged in right. So I turned it on and the backlight on the lcd screen goes on, but no words come up, so I connected an external monitor and that works fine. Any ideas? do I have a bad system board? I also tried to install new memory and it just beeps at me until i put the old memor yback in, and that works fine.

 

[matchu]

Regarding the memory, maybe tell us the specs of your motherboard and the two types of RAM you tested?

No idea about the monitoir. Maybe some wires plugged improperly. What happens if you use your old motherboard instead?

 

[capopp]

memory

is a f055 2g. what was in there is 512mb. the kind of memory I got was a 2gb 2Rx8 PC2-5300S-555-12
HYMP125S64CP8-Y5 AB-C 0814