Black screen after resume from sleep mode (Dell E5410)

[Peng Yu]

I installed ubuntu 10.04 on my Dell E5410, which recently got the LCD
replaced by Dell because the defect in the original LCD.

I don't remember whether the screen was black or not after sleep mode.
But the screen is always black when the laptop is resumed from the
sleep mode.

I'm not sure if this is an problem with ubuntu or it is the problem of
the newly replaced LCD. Could anybody help me on this issue and let me
know how to diagnose?

-- 
Regards,
Peng