Hard Drive Issues

[techo]

OK, so here is the story: my 13" MacBook Pro (2009) was working just fine a couple of days back while I was writing a paper at school. I closed it, went back hope, opened it, watched the beach ball spin for a couple of minutes and decided to restart. Then, the apple would not show and instead of it was a folder with a question mark inside. I thought I could use time machine to restore my system so I started the installation DVD, went to Disk Utilities but my hdd was not listed. I thought the drive has failed so I bought a new one - WD Scorpio Black 500GB 7200rpm. After placing the new hdd I was baffled to find out that I could not do anything with it. I couldn't erase it in disk utility, which came up with the error that POSIX "Cannot allocate memory." I put the hdd in an USB enclosure and could erased it. Then I put it back in the macbook but it didn't let me write on it. I installed OSX on the new drive through the external enclosure and put in back inside but it was unable to boot from it so I put it back in the enclosure and it booted just fine through the USB port.

 

Any suggestions of where the problem might be? Apparently there is nothing wrong with the hdd ( I was even able to repair my old drive, which now works too...)

 

Thank you all!

[strelok1911]

Go to the Apple Store.

It's likely a logic board problem.

 

Or try zapping your PRAM.

[techo]

Go to the Apple Store.

It's likely a logic board problem.

 

Or try zapping your PRAM.

 

I was trying to avoid bringing the computer in since my warranty expired...also tried resetting the PRAM but it didn't help. Is it possible that a some sort of connector or cable has gone bad?