iMac doesn't work after period of no use

[Expertus]

Hey all, my iMac has been at my house alone for 3-4 months while I was away. It was working perfectly fine before I left. When I returned home recently and tried to start it up it took much longer to get to the sign in screen then usual. When I logged in to my account it would show my desktop wallpaper but nothing else. The screen would flash now and then random bits of things and that's all. I could move the mouse on a blank flashing desktop.

Everything I had on the HDD was already copied over to a backup before I left, so I decided I was just going to try and reinstall the OSX and see if that would do anything. When I try to boot from the CD it just gets to the apple logo screen with the loading symbol beneath it and will stay like that for pretty much forever.

Can anyone help me out with this? Thanks a lot ^_^

[chscag]

What year and model iMac do you have? Also include which version of OS X you're running.

[Expertus]

It's an early 2009 iMac Core 2 Duo 3.06 GHz; EMC: 2211
Running Snow Leopard 10.6.6

[chscag]

Try running the Apple Hardware Test on your iMac using your Snow Leopard DVD.

Post back results.

[Expertus]

When I tried booting from the CD the computer either freezes at log in or the screen just goes black. I tried logging in a few times, because every time is different and I actually got the dock and menu bar to appear then the screen shot to grayish blue immediately afterwards.

So I don't believe I'll be able to perform the Apple Hardware Test, but I'll keep trying since it seems every time I turn on the computer something different happens.

[chscag]

As an alternative, try booting the iMac is SAFE boot mode. Hold down your shift key as soon as you hear the POST chime. That boots the machine without most drivers (including sound - so don't be alarmed) and also does a disk check on the hard drive. Let's see what happens.

[Expertus]

I tried going into safe mode, a gray loading bar appeared under the apple logo. The loading bar slowly went to about 2/3 then disappeared. A minute or so later the screen just went black. The screen has now been black for 10 minutes, then restarted again to the apple logo with the chime and all then minutes later went black again.

[chscag]

Things aren't sounding good, I'm afraid. Is your iMac covered by warranty (extended Apple care)? If it is, make an appointment with your local Apple store genius and have them look at it.

Whatever is wrong with your iMac, it's beginning to sound like a hardware problem, one which may require expert repair. It's difficult to say what it could be. It may be something as simple as a bad hard drive, however, removing and swapping out a hard drive in an iMac is a rather difficult and involved task.

[Expertus]

I looked at the whole HDD thing earlier because I felt that was the problem at first, but I believe bringing into Apple was the best bet since there is really nothing you can troubleshoot with.

Thanks again for all the help ^_^