Re: Sony Viao
If there's no light but you can still see the picture, it'd most likely be a backlight issue with the LCD (possibly an inverter issue).
Replace the screen. Usually laptop LCD's run anywhere from $80 to $120 USD.
To be sure it's not a board / video issue (I highly doubt it is, however), just hook an external monitor up to it. If the picture is fine on there, then you can be sure it's definitely an LCD issue.
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