Loading bar on startup twice then shutdown

Hey guys, pretty much, my macbook pro 15" 2006 had been having problems with the fan. It was opened up and cleaned and that solved that problem. Now when I try to turn it on, I get the startup screen (the white one with the apple symbol and the loading circle) but also there's a loading bar. This bar gets up to about 10% then stops and starts again. Then after roughly 10% again, the computer shuts down. I've tried pressing and holding the power button until it beeps when turning it on and all this does is makes it pause at the loading screen (minus the loading bar) and load indefinitely (it was left for hours last time with no change). Does anyone have any idea what's wrong. I'm not sure if it's anything to do with opening it up... Also, I'm on Snow Lepoard and my dvd drive doesnt work (completely different problem though )

Thanks for any help!

The only advice I have - is take it apart again and double check to make sure all the connectors are tight and nothing has been dislodged from the logic board. In other words, go over the previous work that you did.

And, please do not post the same thing twice even if you do use a different title. Your duplicate post has been deleted.