Strange hiss and dim screen at start-up

My imac has begun exhibiting strange symptoms. When I start it up from sleep or being turned off it makes a high pitched hissing/whine noise. The monitor is dim for about 1-2 minutes and I can see horizontal lines on the screen similar to a TV that is not tuning in a station very well. The noise and the lines last about 5-7 minutes. Can anyone tell me what's going on? My first suspicion is that it is a problem with the monitor but I don't know enough about this to be sure.

Welcome to Apple Discussions. In fact, welcome to the Discussions for the new iMac Intel Core Duo!
You may get a better/quicker response by exposing your Mac issues to many more folks with a Mac like yours.
Here is a link to the correct forum for your post;
iMac (CRT)

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I installed memory to my 2007 imac. When I turn the computer on it is making a strange noise and the screen is blank

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Are you hearing beeps?
What was the spec of the RAM?
What was the brand of RAM?
Have you double checked that the RAM is properly seated?

Dimming Screen/No Start up/Spontaneous display shut off

Hi everyone,
I bought my PB G4 in January of 2005, so there are still a few months left on AppleCare, but I've been having major problems due to a little accident involving beer and my girlfriend :P
One evening, we were getting ready to go out to the Campus bar and we were drinking in my dorm room. Stupidly, I put my beer down next to the computer and within about 5 seconds we were rushing to mop it up from the keyboard... Now there were no immediate problems with the computer, but about 2 weeks later, the screen started spontaneously dimming, massive screen distortion (coloured lines everywhere) as well as shutting off. Sometimes I would start up the computer and the screen itself would never illuminate. Now it's been getting worse with the screen shutting off every 5-10 minutes.
I am wondering whether this will be covered by apple care, and what could possibly cause this? I've been looking at the new Imac, but I'm scared of all of the problems I've been reading about. I've been told it might be the Logic board, so if it is, how much would that cost if it wasnt covered by apple care?
I'm sorry my question is basically a novel!
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Hi, Derek. Only AppleCare can tell you what will or won't be covered, but I'd be astonished if they covered a beer spill. Spills can be extremely damaging, especially when they aren't followed up properly. This article from a respected Mac repair service provides some good information about the possible consequences, the repairs that are commonly required, and what you should have done immediately after the spill occurred. Call AppleCare now and get the repair process underway.

Qosmio G20 Beeping a lot and dimming screen - why?

Occasionally my Qosmio G20 starts beeping a lot and reducing the brightness on the screen.
This happens while it is running on AC power and with the power option set to highest level.
Simoultanesly there are some blue lights above the keyboard that starts blinking.
The only way to stop this behaviour is to press the key below the blinking blue light, and then go to the control panel an manipulate the power settings. To do that, I have to change the brightness, press apply, restore the brightness and press apply again. After that it may work for a long time before the next incident.
I have the latest Windows updates, I have an anti virus installed, and I have spyware removers installed, so I don't think any of those are to be suspected.
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regards
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Hi
I would recommend to check the Toshiba power saver.
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Twitter crashing on my iPhone 5 and dim screen

hello guys, so yesterday on christmas eve i was using twitter on my iPhone 5. I was typing a Direct Message, when i pressed the send button twitter randomly closed. So my question is, is something wrong? Another problem I face yesterday was, I was using my iPhone normally then i proceeded to open up siri and this dimmed the screen of my phone like if it was about to be locked. I touched it opened an app and it kept dim until i locked it and unlocked it again. This has happened twice now and to be honest i do not know if I should be worried about it or not. Any help would be seriously appreciated.
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Hi,
My iMac 2007, shut itself off and then restarted. At restart it gave the inicial apple "ping" then got a grey/white blank screen and started to beeb intermittently (tree beeps - pause - three beeps - pause - three beeps - etc).
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Yolanda

It can be failed RAM, unseated RAM or incorrect RAM.
The easiest way to fix it is to replace the RAM. The instructions are in your manual, if you no longer have you manual click the Support link in the upper right of this screen and navigate to the Manuals area.
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ok. i have a HP pavilion entertainment pc dv7 notebook.
1)    For the last 3 weeks my screen would turn off randomly. maybe once every other day or so on. The computer would stay on and my ligths on the keyboard,( VOL bar, Multimedia buttons, Wifi button, Mute button, Caps lock and Num lock) .Only thing that would turn off is my Monitor. Sometimes when it turns off my speakers would make a status sound across the sound bar. But i can be on my computer for hours, or even leave my computer on for days with the screen open and it wont do anything.
2)   then for that last few days i notice when i turn on my computer everything would turn on EXCEPT THE MONITOR. then i hold down the power button and turn it back on and it starts up fine.
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I really rely on my computer so i was considering taking it to a local tech but i wanna know the issue so he doesnt give me some kinda Jive turkey story. I would just start rening a computer from Aarons rent but dont think there computers are any good for my gaming. Starcraft 2, league of legends ecct.

Hi,
Please try a hard reset and see if it works.
1. Power off your laptop
2. Remove the a/c adapter, battery and everything that is attached to your laptop.
3. Hold the 'POWER 'button down on your laptop for about 10 seconds.
4. Plug in the a/c power supply (without battery) and power on.
Please check the following link for more information:
     http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01443366&cc=us&dlc=en&lc=en&jumpid=reg_R1002_US...
Regards.
BH
**Click the KUDOS thumb up on the left to say 'Thanks'**
Make it easier for other people to find solutions by marking a Reply 'Accept as Solution' if it solves your problem.

I have a macbookpro 13 inch (2012) and the screen has started flickering, I'm in Florianopolis Brazil, where should I get this fixed?

screen flickers and just trying to keep myslef calm. I have the applecare warranty and the store finder is only for US. Help!

Few one in this, a peer's forum, will be able to provide you with the information you want. You will want to contact Apple Brazil:
http://store.apple.com/br
You'll find a contact number at the upper right hand side of the page.

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What is the format of the material you are editing, is it variable frame rate?

Screen saver starts up while Safari is streaming

That's it really . . I'll be watching NetFlix or any other streaming video, and the screen saver starts up right on time as if I'd been completely inactive.
What am I missing here ?

Hi,
Open System Preferences / Desktop & Screen Saver then select the Screen Saver tab.
Where you see: Start screen saver
Adjust the slider so the screen saver doesn't activate so soon.
If that doesn't help, open a Finder window. Select your Home folder in the Sidebar on the left now open the Library folder then the Preferences folder.
Move the com.apple.screensaver.plist file from the Preferences folder to the Trash.
Restart your Mac. See if that makes a difference.
Carolyn
Message was edited by: Carolyn

Blue screen on start up. The wheel spin and the blue screen gets brighter for a second, then the blue screen dims and it repeats with the wheel.

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Are you referring to the startup screen which is normally gray with the dark gray Apple logo or are you referring the login screen which is typically blue? If it's the latter you might give this a try:
Clearing Caches to Fix Login Problem
You will need to type some Unix commands. If you are not comfortable with this, I don't know of anything other than a re-install. But if you are careful, you should be OK. I recommend you print this out in a largish mono-spaced font so you don't miss any spaces (or add extra ones). Note that case is important.
Be careful. Some of these commands are dangerous, since you are going to be root.
Start up in Single-user Mode. When this has finished you will see a prompt ending in '#', although there may be other messages. Enter the following commands after the prompt:
/sbin/fsck -fy
Press RETURN. Wait a few seconds for 8-10 lines of output. If the last line says repairs were carried out, repeat this command until you get a message 'The volume <yourdiskname> appears to be OK'. Then continue with:
/sbin/mount -uw /
cd /Library/Preferences
rm com.apple.loginwindow.plist
rm com.apple.windowserver.plist
cd /Library/Caches
rm -r *
cd /System/Library
cd /System/Library/Caches
rm -r *
reboot
Press RETURN after each command.
This should now take you to a proper login screen after the normal boot sequence. You should then Repair Permissions by using Disk Utility (in your /Applications/Utilities folder).
If it's the former then reinstall OS X. For Snow Leopard:
Reinstall OS X without erasing the drive
Do the following:
1. Repair the Hard Drive and Permissions
Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
2. Reinstall Snow Leopard
If the drive is OK then quit DU and return to the installer. Proceed with reinstalling OS X. Note that the Snow Leopard installer will not erase your drive or disturb your files. After installing a fresh copy of OS X the installer will move your Home folder, third-party applications, support items, and network preferences into the newly installed system.
Download and install the Combo Updater for the version you prefer from support.apple.com/downloads/.

Strange dotted screen at start-up

After getting a dead video card replaced at the local AppleStore my iMac now exhibits a strange black dot pattern on white screen just before the log-in window at start up.
The mac was returned to the store, video card replaced again, no change, they decided to replace the
logic board. The dot pattern during start-up now appears intermittently, so I photographed it and found the pattern is the same every time.
• See the pattern here: http://dl.dropbox.com/u/14311256/iMac%20dotted%20screen%20%3F.JPG
The iMac seems to work OK so I am reluctant to return it to the repair shop and be landed with yet another bill. I paid £318.00 for the logic board job but feel this may have been an unnecessary expense.
Q1. what can this dot pattern mean?
Q2. Does it indicate a serious problem?
Q3. Should I just live with it?

I've got the same sort of issue and may have a solution. I noticed it would do it more regularly on startup if my Time Machine external HDD was connected and switched on before powering on the computer. By chance, I forgot to do this a few times and in those circumstances, I switched the external on after the login screen...no dotted white screen before login!
As a result I've done this ever since and no screen issue whatsoever.
It may be that the drive is confusing the iMac during it's startup process, although why that would affect the graphics, I don't know. It works for me, though.
So if you have an external connected all the time, try it without it for a few weeks, only connecting it after you log in.
If you don't have any external peripherals switched on and connected while you get this odd screen, then I'm sorry, I don't know what it could be.
Let us know how you get on, as I'm sure there are many of us out there who would like to know what gets rid of it and what doesn't.
If your Mac works fine other than that, I'd say it's just a glitch in the startup process that doesn't affect the computer. When I was getting the screen you describe, the iMac would operate normally, so I don't think it's anything to worry about.

Grey Screen at start-up - Troubleshoot harddrive and/or logic board?

Hi everyone. Sorry for the lengthy post, but hopefully you can help me - I've spent a lot of time on the boards already, but hoped you could clarify some things.
The problem is my Powerbook will not get past the grey screen at start-up. It will not boot off the 10.5 install disk and I can't eject the install disk to run the hardware test disk. Removing 3rd party ram, resetting PRAM, NVRAM, attempting to boot in 'safe' mode haven't helped. The harddrive is softly clicking/searching.
So some questions:
1) Is it possible that an interrupted time machine backup will bork the drive to the point where it wont boot? (See back-story below). I wouldn't have thought so, but prove me wrong.
2) Should I be able to boot from the install disk if the harddrive is stuffed?
3) If it is hardware, it's either the logic board or the drive. Is there any way to determine what it is (eg: is it possible to do a remote hardware test?)
Edit: Just tried mounting the drive in target disk mode using an iBook, but it wouldn't mount. Powerbook displays a black screen.
Oh, and I should point out that this is well out of warranty and any fixes would have to be cheap : ). Basically I need to determine if it's the drive or the logic board, preferably without having to buy and install a new drive when it may not be the problem.
Any help or advice would be appreciated.
Cheers
- Ben
Here's the back story if it's any help; recently upgraded to 10.5, created a base install disk image of all installed and registered apps (in the event that my drive failed). Copied data etc from the previous system over. It ran fine for a few days. This morning I ran time machine for the first time, left the computer for a while, came back and the screen was black (as if it was just displaying black, as opposed to off). Thinking it was just a display issue (which I've seen before), I put the system to sleep (power button, then 's'), woke it up again; still black. So I forced a shut down (wouldn't allow me to do a normal shut down, because dialogue boxes must have been preventing it) and on boot I got the grey screen.
-------

Hi Ben W. I don't have a good answer for you, but based on your information and what you've done, I think I would try starting the machine after disconnecting the harddrive. That requires taking the top off first, for which instructions are on ifixit.com.
I can conjecture that a blown HD is preventing normal operation, perhaps sucking the power down, disrupting the optical drive, etc. This is purely conjecture, but costs you nothing but your time. If this turns out to be the case, I figure the optical drive should start responding again (hold C key during reboot, etc).

Screen will start to pixelate and error message appears to restart

I have a iMac G5 17". It will boot up, apple start up screen, Mac OS X screen, and then finally Desktop. but about 20 seconds the screen will start to pixelate and kinda "wig out" then it will tint a dark grey and a error message in multiple languages will appear saying " Push the power button to restart". at this moment the screen is completely frozen. all I can do it power it off.
What could this be? Maybe a bad hard drive? Screen? Power source?

Hi...
Better to post your topic in the iMac G5 (PowerPC) community here > iMac (PPC): Desktop Computers: Apple Support Communities
This is the iMac (Intel) community.

I went to use my ipod touch 8GB but it wasn't working, when i looked closer it was on just very very dim. The brightness is turned up all the way and the screen is practically black.. does anyone know how to fix it?

I went to use my ipod touch 8GB but it wasn't working, when i looked closer it was on just very very dim. The brightness is turned up all the way and the screen is practically black.. does anyone know how to fix it?

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.
- Reset all settings If yu can see the screen enough to do it)
Go to Settings > General > Reset and tap Reset All Settings.
All your preferences and settings are reset. Information (such as contacts and calendars) and media (such as songs and videos) aren’t affected.
- Restore from backup
- Restore to factory settings/new iOS device.
- Make an appointment at the Genius Bar of an Apple store since you have a hardware problem.
Apple Retail Store - Genius Bar

Strange hiss and dim screen at start-up

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