Macbook pro issue

Hello mac forums!
i have just recently acquired a dead macbook pro hoping that i could bring it back to life.
The only issue with it on inspection was a flashing folder. I thought it could simply be fixed with installing mac's os x on it. However when i try this the apple logo just hangs there. No spiral. This happens when i try to install off the retail disc, i put disc on an external drive to attempt an install and same thing happens. Im using the 10.6.3 snow leopard disc.

I then thought the hard drive was dead and asked my cousin to bring his macbook over. Luckily he had the same model but different internals so we swapped hard drives over to see what happens. On my cousins macbook with my dead hard drive, i am able to install Mac OS X instantly and flawlessly. When i try to install MAC OS X onto my cousins hard drive using my laptop. It hangs on the apple logo again.

Would anyone know whats going on here?

Welcome to the Mac Forums.

It sounds like the hard drive ribbon cable which goes from the hard drive to a connector on the logic board may be defective. That particular cable is susceptible to a lot of heat when the machine is closed up. That dries it out and can cause internal breaks. Try swapping that cable out.