Grey Screen With Apple Logo

Hello everyone, I just recently started having problems with my iMac.
Details:
- 2006 White iMac with CD Writer/DVD Reader
- 150GB HD
- 1.83GHz Intel Core2Duo Processor
- Recently upgraded 2x1GB Lexar RAM
- OSX Tiger 10.4

Here's the background on what happened. I had started to archive (I think that's what it was..) something onto a USB stick with Disk Utility. I could see that it was going to take a while so I went out for a bit, expecting it to be done by the time I got back. When I did get back, I found that my iMac was frozen and the mouse wouldn't move at all; I couldn't click on anything, couldn't do anything with the keyboard either. So I though "hm, this is strange". I then held down the power button to force a shut down, expecting that it would start up normally. When I went to go start it up again, it was hung up at the Apple logo, no spinner, no broken folder icon, no question mark , nothing, just the Apple logo.

Here's what I've tried (after hours upon hours of googling..):
- Tried unplugging all USB devices (none were attached in the first place except the mouse and keyboard)
- Tried holding down alt/option key to show list of boot drives; after clicking the main one, still gets hung up on Apple logo
- Tried booting from CD; again, just gets hung up at Apple logo
- Tried resetting PRAM
- Tried booting into Safe Mode; still hung up on Apple logo
- Tried booting into Single-User mode; I get to the screen with white writing on it, but it won't let me type in or enter any commands; from what I assume, it goes straight into Verbose mode instead
- Tried Verbose mode, which is how I know that Single-User mode is being skipped..

I don't know what else to do really. Can someone please offer me advice on how to fix it?

When you tried to boot from the CD, how did you do it? Did you hold down the Option key and select the CD, or just use the 'C' key?

When I went alt/option, the disk didn't appear, only my regular HDD did..
When I held down 'C' the disk span in the drive for a while, then eventually stopped.

How long did you let it sit before you decided that it wasn't going to show the disc?

Is the disc damaged or dirty? Is the drive known to work properly?

I let it sit for about 10 minutes or so. I didn't hear the disc spinning anymore, so I figured it wasn't going to work. The disc is pretty much brand new. The drive has worked for me in the past and hasn't given me any problems whatsoever. That being said, any time I've used it previously, it was obnoxiously loud, which I assumed was normal considering the age of the computer.

OK. Since we can't get it to boot with your restore discs, we're very short on tools to try to isolate the nature of the problem.

My suggestion would be to download a copy of Ubuntu Linux:

Homepage | Ubuntu

Burn the disc image onto a disc and attempt to boot off that disc.

If it boots that tells us it's a software problem and a bad OS X restore disc.

If it boots partially and hangs, chances are you have a hardware problem. If it doesn't even offer you the option to boot from the disc, then we know the drive is bad.

I had tried running Ubuntu from a USB stick, but it didn't appear on the list of available boot drives..

Vaeryx said:

I had tried running Ubuntu from a USB stick, but it didn't appear on the list of available boot drives..

Click to expand...

Try it on a disc instead. I've had trouble getting Macs to boot off of Linux ISOs on flash drives that ordinarily boot from generic PCs.

Tried a disc and it just ended up spitting it out.. :S

I also tried the Tiger disc and it popped up the question mark/folder icon.. Then I tried restarting it with the disc in there and it's hung up on the Apple screen again with the disc not spinning anymore

So I just erased the hard drive and installed Snow Leopard via Firewire from a Macbook.. The OS booted up nicely on the Macbook from the Target-disked iMac, but when I went to go and boot it up on the actual iMac, same problem...

Do you have the OEM ram to try? That's my bet, the new ram may have caused some problems, even if it did work for a while.

I do still have it, but it's at home and currently I'm away. So I'll be sure to try it when I get home