iMac Won't Complete Booting

[nollimac]

Fresh install of both El Capitan and Yosemite on the hard drive with two partitions produce the same exact result...not completing the boot process. Can't do Internet recovery and the recovery partition does the same thing...not completing the boot process. Had to install both OS via firewire connected to my MBP.

Then, those third party websites offering the Apple Hardware Test turned out to be empty folders with no diagnostic software in core services. Fsck -fy shows okay.

Wish to know what's happening when booting El Capitan, and the process bar gets to the middle...then makes this jump (the progress bar...sometimes the bar turns white) then completes the booting...I watched it on my laptop, and knowing this would provide the solution as to what's going on with the iMac. Why it's not making the jump...and jump to what?

 

[Fishrrman]

Can you do a "safe boot"?
Can you boot from an external drive with a copy of the OS on it?

 

[nollimac]

Can you do a "safe boot"?
Can you boot from an external drive with a copy of the OS on it?

Thanks Fishrrman for responding...when booting from an external drive with Mountain Lion, it does the same exact thing...spins until it comes to a stop...that's what leads me to think hardware issue...what could it be...fsck -fy says all is good! I wish this forum could provide the AHT CD. Remember, I said it did the same exact think booting the recovery partition (safe mode).

 

[nollimac]

What I am suspecting is that during the booting process windowserver; hence, user is somehow not initiating so the login screen can appear. I just found my old Snow Leopard DVD disk (didn't have the AHT disk) in the storage, and it did the same thing...stopping when it gets to loading windowserver...what hardware is responsible for initiating windowserver, the graphic card?

 

[1411]

Had the same problem, not once but twice, on two seperate MAC Mini 2012. Does the same thing whether booting from internal drive or an external drive. Tried to up grade each to El Capitan from Yosemite. Both times failed. Restored from backup Yosemite and it still does the same thing. Talked to Mac, they said bad logic board. Hard to believe this happened on two seperate Minis, one the was brand new. Anybody have a solution. I have read in others forums this happening, but yet no concrete solution.

 

[nollimac]

So, I had Ubuntu CD with OS 9 and 12...booted just the CD version as well as tested the RAM that turned out good. Ubuntu 9 at least showed the mouse on the screen but no menu...so that seems to confirm my suspicion that the windowserver and the graphic card having issue. The last pic is the full boot up but shows only the mouse (the white dot).

 

[Fishrrman]

What year is this iMac?
The 2011's have GPU problems, I believe...

 

[nollimac]

What year is this iMac?
The 2011's have GPU problems, I believe...

It's a late 2008/early 2009 24" 3.06Hz.