IMac screen issues-turns black then to log-in screen

I own a late 2102 iMac, 21.5 inch. 2.9GHz Intel Core i5 with 8GB memory. Storage=1 Terabyte. Running Yosemite 10.10.1. Several times in the past two months while I am using my iMac, my screen has become very bright, then suddenly switches to a black screen with just the cursor showing. It then switches to the user login screen. Today I was just syncing my iPhone 5S to iTunes. Nothing radical. In the past, I was using Word or sending an iMessage. Instead of logging back on as the same user, I opted to restart. When I restarted, iTunes opened back up as did PowerPoint, which was random since I hadn't been using PowerPoint nor was it even open in the Dock. I have restarted the iMac on several occasions using Command-R and ran Disk Utilities with no problems showing up. Has anyone else experienced the same or similar problem? Is it a Yosemite problem or a hardware problem? Any solutions?

1) You need to Find the crack on Sim 3 game on Google and Copy and replace the File with new crack and problem will get solved.
Try downclocking your >>GPU<<
try lowering it more and keep testing with each one. If you have another power supply test with that(but its HIGHLY unlikely that its your psu). But overclocked cards demand more power as far as i know and it might be getting tough for the psu to handle.
And is the space freeing up on only c drive? It happens all the time. temp files getting deleted and all that. but virus scan and chkdsk wouldnt hurt..................
Take pleasure in knowing that your problem is nothing compared to what most people i stated above are facing. they cant for more than ten minutes. your crash occurred only watch serials once and a after a long time right? see if it happens again. it might get more frequent in which case you problem is very .....problematic.

Similar Messages

What if my iMac boots but turns black

I boot my imac and it turns black and the arrow comes up but does not allow me to use it? any thoughts?

Both of my cameras are broken. Any ways to fix them. Screen turns black then blurry., Both of my cameras are broken. Any ways to fix them. Screen turns black then blurry.Thanks

Hello,
My cameras become blurry and freeze they also turn black. Does anyone know how to fix it? Please help! Thank you

Try:
- Reset the iOS device. Nothing will be lost
Reset iOS device: Hold down the On/Off button and the Home button at the same time for at
least ten seconds, until the Apple logo appears.
- Restore from backup. See:
iOS: How to back up
- Restore to factory settings/new iOS device.
If still problem, make an appointment at the Genius Bar of an Apple store since it appears you have a hardware problem.
Apple Retail Store - Genius Bar
If not covered by warranty
Apple will exchange your iPod for a refurbished one for $149. They do not fix yours.
Apple - iPod Repair price

MBA monitor turns black then returns to normal when I tilt the laptop a certain way

Hi!
Less that 2 months after buying a new macbook air, I started encountering this problem. While working (on a relatively light task - I don't have several applications open, just a few), my MBA screen would suddenly turn black. I noticed one time, the music on my iTunes also stopped playing together with the screen turning black. No, there's no magnet nearby and the laptop was never bumped or dropped. It was super new! And this happens regardless of whether I'm at home or somewhere else like in a mall or cafe.
Three months later, (yes it took me a while because I had to finish a certain project first), I brought it to the apple distributor service center (because it's still under warranty) but it's been more than 7 days now (they promised to give me an update in 7 days), but they still could not give me any report. Could it be a defective unit? I mean, it was less than 2 months old when I started encountering these problems.
Has anyone encountered a similar problem? Do you think I should ask the store I bought it from to replace it? I'm a freelancer and this has terribly affected my work already.
I took a video while this was happening and uploaded it on YouTube. I showed the vid when I brought it to the service center: http://youtu.be/tR9dCji7djI
Btw, I'm not sure about the OS I put below. All I know is that it's not upgraded to Mavericks yet.
Thanks!

Normally, an iPhone will remember what you had your volume set to right before you unplugged your headphones last and set the volume back to that when you plug them in again. Do you have a habit of tuning your volume down before unplugging?

When i take a picture with my ipod it shows up and then it turns black then doesnt save

every time i try to take a pic, screenshot a pic, or save i go to my photos and its shows up BLACK! after that i go back to it its not there pleaseeee heelpp
oh and i did try hard resting my ipod and it didint work plus when i restore back up nothing backs up if you know how to help with anything pleasee help meee

Because the screen aspect ratio is different that the camera aspect ratio. The only way it could fill the screen vertically would be either to stretch/distort the photos vertically or to cut off some of the photos on the sides.

When I go to some of my app they just turn black then go to the home page,

How can I fix this?

Try This...
Close All Open Apps... Sign Out of your Account... Perform a Reset... Try again...
Reset ( No Data will be Lost )
Press and Hold the Sleep/Wake Button and the Home Button at the Same Time...
Wait for the Apple logo to Appear...
Usually takes about 15 - 20 Seconds... ( But can take Longer...)
Release the Buttons...
Note:
Also consider Deleting any Apps you have Purchased / Downloaded but you now never use...

IPhoto photos into iMovie - once rendered, photo turns black

I posted under another thread, but decided this might be better posted to the larger group.
I was working off of an external harddrive when the problem first manifested itself. Dragging a photo from the media pane into the time clip, I saw that the photo turned black and would not display after being rendered.
I moved the drive to another Mac, also an iMac G4 but with a faster processor, and a slightly different experience occurred. Upon starting up the project, when I clicked yes to view the trash, the photos I had been trying to use were no in the trast.
I put a few back and tried to apply the effects, but then the photo turned black. then I grabbed a photo from iPhoto again. The photo would show up but the Ken Burns effect would not stick. If it did stick, the photo turned black and wouldn't display. I saved and quit.
Took my external harddrive to my Powerbook. Had better luck grabbing photos from iPhoto, but no Ken Burns effects worked.
Now I'm back on my original iMac. This time I copied the project to the iMac's harddrive. Now there is another experience - a little closer to what I want but still not what I'm used to:
I added the photo to the timeline, it rendered itself to black again. Much frustrated sighing.
However, I had added some music to the timeline in the interim periods and just decided to view what I had. Lo and behold the black photo displayed with the Ken Burns effect. I added a couple more photos and they began to behave as they always have. You can see the photo in the time line. The black one is still black.
All this is quite unsettling. I plan on doing a project with 60 students in October and need to know if anyone thinks this is a bug or what? Thanks for any insight.

I am having the same problem images turning black when brought into the timeline Started when bringing in Photos from APERTURE 1.5. Thought this program was the problem so, I imported the same images into iPhoto. The problem does seem to "fix" when transitions are added , but this makes it difficult to edit and rearrange images. The hard drive is formatted Mac OS Extended (journaled). Shooting a Nikon D-70; D-200. Images a 2 - 5MG. Most confusing it is not consistent happens to some images and not others. Same problem happened when images were imported to iMovie.
ANY SUGGESTIONS MOST APPRECIATED, TRYING TO COMPLETE A BIG PROJECT THIS WEEK.
THANK YOU

Firefox 8 turns black on opening.

When opening a new window, the border turns black then goes back to normal. This slows down the browser a bit.
[http://i.imgur.com/DugeR.jpg Picture]

This - http://www.google.com/firefox - is the old Firefox Start Page used by the Firefox 3.6 and earlier versions of Firefox, I don't think it is being maintained.
Starting with the Firefox 4 version, Firefox is using a "local" Start Page with the address of '''about:home'''. It looks similar to the old Start Page, but it isn't exactly the same.

Imac G5 grayish screen with apple in the middle and then it turns black

Hey all,
Im really stressed about my Imac. Its about 3.5 years old. I never had a problem with it until today. I turned it on and all of a sudden it went grey with an apple in the middle. Then it turns black! So what can be wrong with it? Does this mean I lost everything on my computer. I dont have any back up files on my Imac cause I never thought this would happen. Im worried cause I have all my photos on it and music. What should i do? My main thing is that I don't want to lose my stuff on my Imac.

You could see if the suspect iMac can be
started up in FireWire Target Disk Mode.
Connected to another Mac, with a proper
FireWire cable, the other Mac could see
the hard disk drive in your suspect Mac
as just another external hard drive; and
you could try to reclaim files from there
into the healthy Mac's drive or burn the
files over onto removable disc media.
What computer are you using to post here?
{Although the thread you are in now does
pertain to the 'first series' flat panel G4
iMac, the symptoms and some issues
behind them would not be dissimilar in
a G5 verses those in a G4...}
Will the computer start up in SafeBoot?
That's with the Shift key held awhile
until the screen appears, and a login
window is there. If you can do that,
then you may also be able to repair
disk permissions and see if it would
restart. And, you could also see if
the computer can start from the OS X
installer disc; to run 'repair disk' or
also to try to run Startup Manager
and see if you can get the Apple
Hardware Test to start the Mac.
There may be some problem, but to
identify the cause will involve some
troubleshooting. My immediate issue
in this question is my lack of sleep.
So, I may have to mentally shut down
for a time and reboot tomorrow!
You could try and see if resetting the PRAM
can help this, since it is non-invasive:
Try resetting the P-RAM. Hold optionapple+pr
keys down until you hear the boot chime 3 times.
You can invoke the Startup Manager on bootup
by holding down the Option key to see choices
to include a Hardware Test on an installer disc.
Good luck & happy computing!

IMac keep shutting down black screen then have to hold power button down then turn it on again i did this 4 times in all of a period of 5 minutes what to do ??

iMac keep shutting down black screen then have to hold power button down then turn it on again i did this 4 times in all of a period of 15 minutes what to do ??

Hmm. The problem still may be the RAM - Apple buys the RAM it puts in its machines from third-party vendors (usually Hynix) so it could be a RAM problem.
There are a couple of things that you can do yourself before taking your machine into an Apple Store or an AASP... download and run an application named Rember that will run a RAM test for you - let it run for a couple of hours or even overnight. If it turns out that your RAM is faulty, Rember will let you know. If it is faulty, then you have a couple of options - replace the RAM yourself or (particularly if you're under warranty still) take the machine to an Apple Store or AASP and have them replace the RAM.
If Rember finds no fault with the RAM, then you'll need to take it into an Apple Store/AASP and get a free diagnosis on the machine. Three beeps do usually indicate faulty RAM, but if it tests good with Rember you likely have another problem - it could be something as simple as the RAM, somehow, not seated correctly or signs of another hardware problem.
Run Rember first... call back with results.
Good luck,
Clinton

I had a problem with imac screen going black. apple store diagnosed prob with video card which they replaced. Brought it home, turned it on (have done this 4 times) it starts up, wheel turns, there is a long bar at bottom which fills up, then it turns off

I had a problem with imac screen going black. apple store diagnosed prob with video card which they replaced. Brought it home, turned it on (have done this 4 times) it starts up, wheel turns, there is a long bar at bottom which fills up, then it turns off

Apple guarantees their work, take it back.

21.5 mid-2011 iMac screen keeps glitching out and then eventually goes black.

At the end of August 2011 I purchased a 21.5-inch iMac and just last week (8 or so months later) the screen started to glitch everywhere and then eventually turned black. It has been happening quite regularly and has become quite an issue. Before then it had been running perfectly, and we had had no problems at all. However when the screen goes black (as if it was asleep) you could still hear things playing in the background (such as the noise that the volume key makes when you press it on the keyboard). We have eliminated all possible interference problems (turned off: wifi, phone's, TV, lamps and even the fish pump) and have also had it tested by license technicians for software and hardware issues (which came back clean). So then they replaced the screen thinking that was the only other possibility, and when we brought it back home it started to do it again. I have no idea anymore and I was hoping that someone could tell me what might be going on, otherwise I will get it replaced under extend Apple Care warranty.
Thank you and the main specs are below:
2.7Ghz quad-core Intel Core i5 processor
4GB Ram
1TB hard drive
AMD Radeon HD 6770M graphics processor with 512MB of GDDR5 memory

Heloo,
Don' turn off the Fish Pump!
~BDAqua
http://www.yelp.com/biz/b-and-d-aquarium-seattle
Ray C was a bit out of touch & was speaking of a place a half mile away that supports "Growers" for Hydroponic stuff... LOL
Anyway...
Get Temperature Monitor to see if it's heat related...
http://www.macupdate.com/info.php/id/12381/temperature-monitor
iStat Menus...
http://bjango.com/mac/istatmenus/
And/or iStat Pro...
http://www.islayer.com/apps/istatpro/

IMac screen is black and won't turn on

I got a 27" iMac (intel) a couple months ago (mid-year 2010) and sometimes the screen won't start up after it goes to sleep. Most of the time, I will leave the computer and the screensaver will start then the display will turn off and go black. When I return and hit a button on the bluetooth keyboard or move the Magic Mouse around, the computer will come out of sleep, display will turn on, and everything works the way it's supposed to. However, every now and then, the screen will go to sleep (turn black) and it won't turn back on when I hit the keyboard and move the mouse. I can just barely hear the fan still working, so I know the computer is on but asleep. Even when I hit the power button or hold it nothing happens, it won't even restart. I have to physically unplug the power cord and replug it back in then hit the power button to get the computer to start up again. I have moved the computer around to different outlets and even tried it at a different house, but this issue still occurs. Am I doing something wrong with the Energy Saver settings or is there just something wrong with my computer?
Thanks!

Hi, I hope you find this information useful:
A few years ago, we purchased iMac 27" 11,3 (Mid-2010) (with i7 2.93Ghz, ATI 5750 1GB VidRam, etc.) for our offices and software development team. They were originally shipped with Snow Leopard and worked as expected and without any problems. However, a year later, we upgraded to Lion and all of machines immediately exhibited the same problem: the screen would go to sleep by itself and would require a hard reboot or sleep on/off. (Only the screen was asleep and the rest of the iMac continued to function; this was confirmed by screen sharing to the machine.)
Due to the severity and impact on our business, we immediately contacted Apple and their genius bar staff in New York/SoHo. They were unable to determine the root cause, so they replaced all of the logic boards, video cards, and screens, and got us back online asap. This resolved the problem, but we were curious to know why. After days of rigorous testing, we concluded that the issue is caused by a bug in MacOS. Specifically, faulty Kext files (Kernel Extension files extend the functionality of the MacOS Kernel) for the ATI drivers. So, why did the replacing the hardware work? We think that the Kext files that were released and distributed with Lion (and later MacOS versions) correctly supported the newer hardware revision of the replacement components, but not the older ones.
If you're experiencing this problem, short of replacing the components or waiting (for another 3+ years) for Apple to hopefully fix their OS software, you can lessen the effects and be able to recover faster by doing the following: (Please bear in mind that these are not permanent fixes.)
Turn on "Hot Corners" and assign one corner to "Put Display To Sleep". When your screen goes to sleep, move your mouse (which still works) to that assigned screen corner for a second, then move it again. This will wake your screen. You may have to do this a couple of times, but it's much faster than a hard reboot or a sleep on/off for your iMac.
Turn the brightness of your screen to a low setting (10%-15% of the total brightness).
Turn on screen sharing, so you have a last resort method of accessing the machine.
If you're not convinced that it's a MacOS software problem, then do what we did and see for yourself; install Windows 7, Windows 8, or Linux via Bootcamp or as the only OS on the iMac. Those operating systems and drivers worked flawlessly for us; the bug does not occur and the screen does not go to sleep, but if you dual boot and switch back to MacOS, the bug reappears because the iMac is loading faulty Apple MacOS software.
Good luck!

Screen turns black suddenly, then re-emerges within a second

Hi,
here's a new strange issue with my new Asus Eee PC: Recently, and perhaps it's because some updated packages, the screen turns black totally without warning, and shows up again as if nothing has happened. That is, no matter what I currently do, at any time the screen turns completely black (not even dark or something like that) for just a second, and appears again simply. Nothing strange can be noticed, my session just continues as if this didn't happen.
I haven't had any success finding the triggers for that behaviour, it seems so accidentally ... be it browsing the web, right after session startup and everything else. What I've noticed though is that it happens only a single time within a session and both on battery and on power.
Graphic chip is an Intel Mobile 945 GME, and I'll add my xorg.conf as soon as I can. Strangely, there is no note in Xorg.0.log either.
What I'm currently doing now is checking whether this also happens in a GNOME session. Sounds strange, but the first time I've noticed this behaviour is with Openbox, and the last days I was using only Openbox. Still I don't know whether Openbox might cause this problem.
I'd be very glad if someone could give me some hints on tracking down this issue. Perhaps this also happens at someone else's machine.
Gratefully,
Leye
EDIT
Alright, here's my xorg.conf:
Section "ServerLayout"
Identifier "X.org Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection
Section "Files"
ModulePath "/usr/lib/xorg/modules"
FontPath "/usr/share/fonts/misc"
FontPath "/usr/share/fonts/100dpi:unscaled"
FontPath "/usr/share/fonts/75dpi:unscaled"
FontPath "/usr/share/fonts/TTF"
FontPath "/usr/share/fonts/Type1"
EndSection
Section "Module"
Load "record"
Load "dri2"
Load "glx"
Load "dbe"
Load "extmod"
Load "dri"
EndSection
Section "InputDevice"
Identifier "Keyboard0"
Driver "kbd"
EndSection
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/input/mice"
Option "ZAxisMapping" "4 5 6 7"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
EndSection
Section "Device"
### Available Driver options are:-
### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
### <string>: "String", <freq>: "<f> Hz/kHz/MHz"
### [arg]: arg optional
#Option "NoAccel" # [<bool>]
#Option "SWcursor" # [<bool>]
#Option "ColorKey" # <i>
#Option "CacheLines" # <i>
#Option "Dac6Bit" # [<bool>]
#Option "DRI" # [<bool>]
#Option "NoDDC" # [<bool>]
#Option "ShowCache" # [<bool>]
#Option "XvMCSurfaces" # <i>
#Option "PageFlip" # [<bool>]
Option "AccelMethod" "exa"
Option "MigrationHeuristic" "greedy"
Option "DRI" "True"
Option "NoDDC" "True"
Option "XAANoOffscreenPixmaps" "True"
Option "EnablePageFlip" "True"
Option "RenderAccel" "True"
Identifier "Card0"
Driver "intel"
VendorName "Intel Corporation"
BoardName "Mobile 945GME Express Integrated Graphics Controller"
BusID "PCI:0:2:0"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 1
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 4
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 8
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 15
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 16
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
Modes "1024x600
EndSubSection
EndSection
Section "Extensions"
Option "Composite" "Enable"
EndSection
Last edited by Leye (2009-06-16 14:31:52)

Good to know that there are other people with the same issue as well. As long as I use Openbox, I've deactivated gnome-power-manager, though I hope this will go away with new updates. In the meantime, deactivating gnome-power-manager is o.k.
I don't know though what you should do if you rely on the whole GNOME desktop.

When I turn on my iMac, it shows a black screen and says 'No bootable device - enter boot cd and press any key'. Not sure how to fix this.

When I turn on my iMac, it shows a black screen and says 'No bootable device - enter boot cd and press any key'.
I'm not sure what to do, I did not recieve a cd with my mac to boot it up (I ordered it online).
Also I can't find my harware serial number (I've tried many times to input what I thought it may be from my receipt). I saw that I need this number to contact apple support, my 90 day complimentary support is still valid so I wish to contact them.
I don't know much about apple products as this is my first apple computer so any information is helpful.

Hold down the Alt/Option-key at startup of your iMac to get the Boot Selection screen.
From that choose to boot into OSX.
Once in OSX go to System Preferences then Startup Volume and reset your OSX to be the default.
The new iMacs have OSX 10.7 Lion preinstalled and don't come with any CD/DVD anymore.
Instead OSX Lion includes a new feature called "Lion Recovery".
Have a read here About Lion Recovery
Stefan

IMac screen issues-turns black then to log-in screen

Similar Messages

Maybe you are looking for