iMac Graphic Issue - Crashes

Thank you! Let me just run the app an then post the results.

I cannot pass the Apple logo, now it just stays at the grey screen without any progress bar, just a grey screen. Before that, the computer was stuck in a reboot loop.

Thank you for all your replies, they have been really helpful.

I guess that's our end, the recovery partition cannot start. I managed to select the Recovery Partition by pressing the Option key, but it just stays at an apple logo.

WAIT...

While i was writing this "last" message, the system booted normally, meanwhile im running EtreCheck.. It`s really weird. Let me just reply to you on an other message the diagnostic. What the heck is going on!?

EtreCheck version: 2.5.3 (206)

Report generated 10/8/15, 4:05 PM

Download EtreCheck from http://etresoft.com/etrecheck

Click the [Click for support] links for help with non-Apple products.

Click the [Click for details] links for more information about that line.

Hardware Information: (What does this mean?)

iMac (27-inch, Mid 2011)

[Click for Technical Specifications]

[Click for User Guide]

iMac - model: iMac12,2

1 3.1 GHz Intel Core i5 CPU: 4-core

8 GB RAM Upgradeable

[Click for upgrade instructions]

BANK 0/DIMM0

4 GB DDR3 1333 MHz ok

BANK 1/DIMM0

4 GB DDR3 1333 MHz ok

BANK 0/DIMM1

Empty

BANK 1/DIMM1

Empty

Bluetooth: Old - Handoff/Airdrop2 not supported

Wireless: en1: 802.11 a/b/g/n

Video Information: (What does this mean?)

AMD Radeon HD 6970M - VRAM: 2048 MB

iMac 2560 x 1440

System Software: (What does this mean?)

OS X Yosemite 10.10.5 (14F27) - Time since boot: less than an hour

Disk Information: (What does this mean?)

WDC WD1001FALS-403AA0 disk0 : (1 TB) (Rotational)

EFI (disk0s1) <not mounted> : 210 MB

Macintosh HD (disk0s2) / : 999.35 GB (566.71 GB free)

Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

OPTIARC DVD RW AD-5680H ()

USB Information: (What does this mean?)

Apple Inc. FaceTime HD Camera (Built-in)

Mitsumi Electric Hub in Apple Extended USB Keyboard

Mitsumi Electric Apple Extended USB Keyboard

Apple Inc. BRCM2046 Hub

Apple Inc. Bluetooth USB Host Controller

PixArt USB Optical Mouse

Apple Internal Memory Card Reader

Apple Computer, Inc. IR Receiver

Thunderbolt Information: (What does this mean?)

Apple Inc. thunderbolt_bus

Gatekeeper: (What does this mean?)

Mac App Store and identified developers

User Login Items: (What does this mean?)

iTunesHelper Aplicación (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)

Other Apps: (What does this mean?)

[running] com.apple.xpc.launchd.oneshot.0x10000002.EtreCheck

Internet Plug-ins: (What does this mean?)

Default Browser: Version: 600 - SDK 10.10

QuickTime Plugin: Version: 7.7.3

3rd Party Preference Panes: (What does this mean?)

None

Time Machine: (What does this mean?)

Time Machine not configured!

Top Processes by CPU: (What does this mean?)

17% TMHelperAgent

7% kextd

3% fontd

3% mds

3% WindowServer

Top Processes by Memory: (What does this mean?)

627 MB kernel_task

385 MB mdworker(13)

205 MB com.apple.WebKit.WebContent(2)

131 MB Safari

115 MB mds_stores

Virtual Memory Information: (What does this mean?)

3.11 GB Free RAM

4.89 GB Used RAM (1.50 GB Cached)

0 B Swap Used

Diagnostics Information: (What does this mean?)

Oct 8, 2015, 03:59:33 PM Self test - passed

Oct 7, 2015, 08:37:56 PM /Library/Logs/DiagnosticReports/com.apple.photomoments_2015-10-07-203756_[redac ted].cpu_resource.diag [Click for details]

Oct 7, 2015, 12:12:54 PM /Library/Logs/DiagnosticReports/installd_2015-10-07-121254_[redacted].cpu_resou rce.diag [Click for details]

Oh! That should be the problem... I'll go tomorrow to the Mac Store, i just called and told me to do this. I hope i can get this replacement. Thank you so much for all your replies, you have been really helpful!