HD, Windows or BIOS problem?

It looks like I may have a major problem with my HD. Here is the sequence of events:1/ One of my GF module did not work because it was not detected by my GF config. software, I resolved that problem. And I had to restart Windows so as to install the new GF module.2/ To restart Windows, I simply selected "restart" and Windows initiated its close down process, that lasted for ever (read more than 10mn), I then decided to press the restart button on my PC so as to speed up the process.3/ When restarting my PC went through the BIOS very, very, very slowly as a matter of fact, after 15 mn it is still going on when I type these lines.I don't know what that means, I never had a hard disk breakdown in 20 years and I hope this is not the sign of one. Can any one shed some light and guidance on this? Many thanks in advance. Setup: Intel I7 940 4GB RAM, Asus PT 6 Deluxe ATI HD Radeon 4870 1GB