i bought a 4090cds about 2 weeks ago. the display looked a little funny(fading round edges and colours didnt look right) even when i installed the correct drivers the display when adjusted contrast either went too bright or too dark. i had a replacement off ebay from a 4070cds. the screen i had was still inside the plastics it was a complete lid with top part of the laptop still attached with the two plugs coming through the bottom so to save a lot of dismantling to see if screen i bought worked i removed keyboard and cover piece that covers the screen connector that connects to the mother board. I switched on it seemed a little better so i unplugged it (still switched on) when i plugged in the original connector (inverter plug first then bigger plug for display) the screen now is white with no display. the backlight is working but nothing else. the laptop works when a normal monitor is plugged into the back of it. is there any buttons ive pressed on the keyboard to disable the display? ive tried the FN and f5 button still getting a white screen (backlight)
any help would be great
THANKS

a really big thank you to all who replied but ive fixed problem with no help from no one!!!!!
i thought there would be someone out there with knowledge
even my mate who is autorised tosh laptop repairer was baffled. but with a good knowledge of electronics ive worked it out my self and it was no loose connections whatsoever
i wont be telling anyone my secrets as from this i can make big money