MBP Black screen, no boot, disk working, no keyboard lets

I have a first generation late 2006 core2duo. Today it unexpectedly stopped booting up. The first time I turned it on it booted slowly but the screen never came on. I got it to reboot once in safe mode, although it took a long time to boot up. After a restart it hasn't booted again.

Here are the symptoms:

1. After initial boot spin-up sound, no chime, there is a pause for several moments, then the disk and fan slowly wind up.

2. The screen remains blank. If I plug in the USB mouse it flashes every ten seconds or so, like it does in sleep mode, but never comes on.

3. The disk itself is making considerable noise under the fan. I can here it chugging frequently, but it's not a steady sound, it's definitely chugging on different bits as if the system is doing something.

4. The keyboard lights do not come on, the num lock, etc.

5. The little lite below the latch glows steady.

A few things I know and have done:

I have an ATI graphics card, not nvidia, per the nvidia problem.

I have tried to reset the pram, although with the slow boot up and lack of chime/screen, I can't really tell if that's doing anything.

I've reset the SMC controller or whatever, as far as I can tell.

It will not boot into safe mode anymore. It doesn't seem to be responding to any of the start up key combinations. The keyboard seems, for all intensive purposes, to be disabled. Also, the boot up pauses at first and then winds up so slow that it seems like the key presses are down before the system ever even knows they exist.

I'm beyond frustrated. As I understand, things like the logic board, etc would cause the disk not to spin up and chug along like it's doing something? This is my only machine to work with and I'm on some project deadlines. Anything anybody can suggest is hugely appreciated!!

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Ok, after three hours of trying to get this thing to boot (I'm house sitting, not at home with full arsenal of externals) I plugged in my one external drive, which I think has a backup on it, though I'm not sure its bootable. So I plug the drive in and start the computer up with the option key held down, and the screen comes on right away and boots with my disk options, BUT the only option is my hard drive. I'm about to run verifications and disk repairs.

WHY would just plugging in a USB drive, with apparently no bootable system on it cause my MBP to suddenly boot up after hours of trying?

 

Unless they release a new pro machine this year I will be forced to go to the dark side. I have only ever personally owned apple products for the past 17 years and never thought I'd be considering spending 4 grand on a pc instead of a mac. And yes, I do digital compositing and 3D work.

But seriously, can someone tell me why plugging in a USB drive would suddenly cause the machine to boot? I'm very afraid that this isn't going to last.

 

Anyone? Beuler?