iMAC 2011 27" which doesn't boot, it doesn't see any boot volumes.

[Joolsc]

I have a iMAC 2011 27" which doesn't boot, it doesn't see any boot volumes.

If I boot normally, it displays the Folder with question mark symbol.

If I boot normally with a OSX Lion dvd inserted, it displays the prohibitory sign.

If I boot from OSX / Internet Recovery it goes to the Apple Logo, spins for 30s then a quick flash on the screen, then stays white screen. I can never get the OSX Utilities menu to show up.

I ran the AHT extended test, no problem as found.

At this point, is it simply a failure HDD or a major part that I need to replace like the GPU / Logic board?

It does have a 6970M 1GB GPU, can this affect it?

 

[Samuelsan2001]

Sounds like a new HDD is required although it's possible it's a SATA cable.

 

[Joolsc]

Sounds like a new HDD is required although it's possible it's a SATA cable.

I managed to create an external hdd with bootable El Capitan.

By holding down Option, I can boot from:

1) external hdd -> apple logo -> 2/3 of the way it flash then white screen
2) external hdd -> apple logo -> 2/3 of the way whole screen went blue with black strips
3) external hdd -> apple logo -> 2/3 of the way it flash with a 2cm row of random colors then white screen.

Should I purse further to get it fixed? even with the internal hdd failed, I was hoping to run osx normally with an external hdd.