I replaced my Macbook Pro 15", 1st gen, 80g internal hard drive with a 500g samsung internal hard drive. I have been using it successfully for over six months. In the past three days I have been getting the spinwheel more and more often to run basic programs, until today when I can't even do that. At this moment the drive is unrecognizable, and I can't even boot the computer. When I power up, the blinking folder and question mark appears. When the internal disk was still visible, I used disk utility from my OSX installation disk and repaired permissions. To no avail. Now the disk is not even visible! Any help or suggestions are greatly appreciated.