MacBook Pro computers prior to 2012 Retina are likely to suffer a no backlit syndrome. You may like to call it GPU failure. And it may happen in a special pattern where system itself is unable to rectify such issue.
No backlit + no external video = logic board malfunction
You can hear the chime. But the display will have no backlit. When you tilt a bit or use a flashlight against Apple logo, you will see that your Mac actually turns on well. This is a fascinating malfunction of the GPU.
Is there a way to fix no backlit issue?
There is a way to fix such no backlit issue. Many service shops around you may call it GPU reflow which is a nasty service in itself but it fixes temporarily. But we recommend to approach a service store that replaces GPU. Reflowing GPU may quickly bring the issue back but replacing GPU will have a lasting usability.
How about no external video but there is internal display?
There are chances that you may not have external video but the internal display is still functioning until the GPU services load. As soon as the GPU required services or drivers begin to load, your Mac will either freeze or turn to blank screen. Fans may go high or the Mac may stay at gray screen. Sometimes you may also view patters of horizon or vertical lines. These are all expected symptoms of failing GPU.
What’s the solution of no backlit no external video?
Do not go for cheap reflow services. The issue will come back as soon as you begin to render graphics intensive tasks. If you are not quire ready to replace the logic board, get quote from a service shop that offers the GPU only replacement service. Such service will cost quite near to the new logic board replacement cost but the new GPU is expected to be more heat efficient hence sustain more aggressive workloads.