Computer won't load past grey screen with Apple logo, even with OS Disc

Take it in for service.

If the computer will not boot from an installer disc so you could erase the hard drive and reinstall OS X, then I don't know what else you can do.

Do you have another Intel Mac, and do both of them have Firewire ports?

repeatuntilfalse wrote:
dang, you really think there's nothing i can do on my own?

Hi repeat, and welcome to Apple Discussions.

Faulty/incompatible/loose RAM can cause all kinds of startup issues. Is your RAM original Apple-supplied RAM? If not, it's a bit more likely to potentially be an issue. If you want to try something before bringing it in to a repair shop, pull one RAM module, try booting, switch RAM slots, try booting, repeat with other RAM module. You could also try running the Apple Hardware Test from the proper install disc, although it may not boot from that either. Aside from that, I can't think of anything else but to bring it in for testing, as Kappy has suggested (the usual diagnosis is bad logic board/big bucks).

repeatuntilfalse wrote:
dang, *you really think there's nothing i can do on my own?*

If you have AppleCare, you paid for coverage so that you won't have to worry about "do on my own."

Well if you do then turn both computers off. Connect a Firewire cable between them. Boot your computer into Target Disk Mode. After the TDM screen appears boot the other computer normally. If your drive is accessible it will show up as a disk icon on the Desktop of the other Mac. You can then access your files and transfer them to another hard drive.

Then open Disk Utility. Your drive should appear in the sidebar list. Select the drive entry (mfgr.'s ID and drive size) then click on the Partition tab in the DU main window. Set the Partition Scheme drop down menu to one. Set the Format type drop down menu to Mac OS Extended, Journaled, then click on the Partition button and wait for the process to complete.

Your drive should now be OK assuming it's not mechanically damaged. Eject the drive from the Desktop as you would eject any removable drive and disconnect the Firewire cable. Shutdown your computer. You can now boot from the installer disc and install OS X.

repeatuntilfalse wrote:
i cant get the cover off to mess with the ram though.

Detailed/illustrated directions can be found at ifixit.com, macsales.com, youtube, etc. If you want to attempt it, make sure you have the correct size of driver so as not to damage the screw heads. After viewing the directions, if you're not comfortable with the procedure, probably best not to try it, and just take it to a repair shop.

I would recommend trying the following before reformatting (if you care to do so):

1) hold down command + s (simultaneously) to boot into single user mode

2) wait for the system to load the text interface

3) type the following, exactly: fsck -fy

4) hit enter and wait for the process to finish

5) type the following, exactly: shutdown -h now

6) hit enter and wait for your machine to shutdown

7) power on the system and immediately hold down option + command + r + p until the system beeps then restarts and beeps again

8) let go of the option + command + r + p keys after the second beep

9) wait to see if the computer tells you to reboot yet again

Oh god... I've been having the same problem. If only I knew how to make it stop. I've been going out of my head since June 30 trying to figure this out. Here are some of my related posts:

http://discussions.apple.com/thread.jspa?threadID=1916253&tstart=0&messageID=118 22729#11822729

http://discussions.apple.com/message.jspa?messageID=11822666#11822666

In my case, I "seem" to have fixed the problem simply by switching back to the original RAM (2 modules at 1 GB each). My new RAM passed all of the memory tests I threw at it over several hours, but it didn't reveal any problems. However, since switching back to my old RAM I've been running nice and stable for over 8 hours.

Quick question: how much RAM is in the failing machine?