Macbook booting up to black screen

Hello!

I have a 2007 Macbook and after putting it in sleep mode overnight, it wouldn't boot up properly when I came to use it in the morning. The keyboard is functional (I can hear the noise when I press the volume buttons) and I hear the start up chime - but then the screen will go black and all the lights will go off. It will sometimes load up to the login screen and then the screen will go black. It doesn't switch off, I have to shut it down by holding the power button.

I've reset the SMC and PRAM and it has done nothing. I was wondering if anyone had any idea what the cause may be and how much I will expect to pay to fix it? As it is fairly old and the DVD drive is broken, I'd be tempted to buy another laptop if it works out to be very expensive to fix.

Any help or advice you could offer would be greatly appreciated!

It's hard to determine what could be causing the screen to go black like that. It could be the hard drive or something else. Without a working optical drive, you have no way of doing any viable trouble shooting. If you do decide to let Apple look at it, make sure you ask for a repair estimate first. A MacBook that old is only worth several hundred dollars even when in good condition. You certainly don't want to spend too much for repairs.