My imac screen is flashing after startup?

I may have a problem with my imac's screen flashing around the dock right after blue screen it shows up.
The dock will flash for a 1sec or 2sec and thats it.
Do i need to test the memory because i did install Hynix 2 X 2GB PC3-8500S DDR3 and they where from a macbook pro?
Will i need to take them out and leave in 2 original sticks then restart the imac to see if it corrects the problem?

A screen flash is not related to RAM. It's some other issue, which could be software or hardware related. You can start by doing some basic trouble shooting including restarting in Safe Mode and doing both a SMC and PRAM reset. It's OK to do each of these actions multiple times and it may be necessary to do them multiple times. If they don't help you can try some other things which we won't address yet.
iMac
SMC & PRAM Resets
SMC RESET
Shut down the computer.
Unplug the computer's power cord and all peripherals.
Press and hold the power button for 5 seconds.
Release the power button.
Attach the computers power cable.
Press the power button to turn on the computer.
PRAM RESET
Shut down the computer.
Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
Turn on the computer.
Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
Hold the keys down until the computer restarts and you hear the startup sound for the second time.
Release the keys.

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Hi patrickbryant,
Thank you for participating in the Apple Support Communities.
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Please read this whole message before doing anything.
This procedure is a test, not a solution. Don’t be disappointed when you find that nothing has changed after you complete it.
Step 1
The purpose of this step is to determine whether the problem is localized to your user account.
Enable guest logins* and log in as Guest. Don't use the Safari-only “Guest User” login created by “Find My Mac.”
While logged in as Guest, you won’t have access to any of your documents or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this behavior; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.
Test while logged in as Guest. Same problem?
After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.
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Step 2
The purpose of this step is to determine whether the problem is caused by third-party system modifications that load automatically at startup or login, by a peripheral device, by a font conflict, or by corruption of the file system or of certain system caches.
Please take this step regardless of the results of Step 1.
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Safe mode is much slower to start up and run than normal, with limited graphics performance, and some things won’t work at all, including sound output and Wi-Fi on certain models. The next normal startup may also be somewhat slow.
The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.
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Try this:
Reinstalling Lion/Mountain Lion Without Erasing the Drive
Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
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Yes it shouldn't be that difficult. You can tell her to try some basic resets too, they won't hurt and might help. First is try resetting the SMC and PRAM. It's OK to do these multiple times, also trying to restarting in Safe Mode may work. For the SMC and PRAM resets I will print the instructions below. To do a Safe Mode restart, hold down the Shift Key when the startup tone is heard, if she can see a progress bar appear release Shift key and let it fully boot. Then restart normally to test. If the screen is still black then the LCD or the graphics card has probably failed. In that case it's probably best to just replace the whole computer as the expense of repair will be difficult to justify.
SMC RESET
Shut down the computer.
Unplug the computer's power cord and ALL peripherals.
Wait 15 seconds.
Attach the computers power cable.
Wait another 5 seconds and press the power button to turn on the computer.
PRAM RESET
Shut down the computer.
Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
Turn on the computer.
Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
Hold the keys down until the computer restarts and you hear the startup sound for the second time.
Release the keys.

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I started it up in safe mode, which surprisingly worked. I had a boost in moral at this point, because all my files also loaded. I started windows normally. I had the black screen thing again, but after a while I had a program pop up. I proceeded to open
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I seen others who had similar issues, but I could open task manager and start up explorer.exe, so I am a special snowflake among these other ones.
I don't quite know what a good way of going about the issue would be, should I system restore? Is there a problem with the shell? I don't exactly know what I should do, any sort of information should help.
Some other possibly unrelated things:
Recently, my driver has been crashing (should I update that, is that the reason this is happening?)
My files are all intact, I saved important ones. What should I do?

Nevermind. I took matters into my own hands and it took only a single system restore to fix the issue!
Crisis averted!
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I have a mid-2007 iMac. When anyone is on the computer for approximately 1-1.5 hours, the screen goes black and we cannot get out of this. There are no time restrictions or power-saver settings on. Can anyone help me with this issue?

You cannot do anything with the iPad until you do as instructed by the iPad and connect to iTunes on a computer.
You probably need to restore the iPad and the only way to do that is via iTunes on a computer.
Take it to an Apple Store and ask for help at a Genius bar or take it to a friend's house that is running iTunes on their computer and try to restore it.
You will lose all of your data and settings now because you never backed the iPad up in the past.

IMac screen blue flashing tint - please advise

Please view the video of what the screen is doing because , well, just view it please, you will see.
http://www.islandsmoothiebeachtro.com/iMacScreen.avi - 17 mg avi
no I am not playing with any wires. and yes it does look pretty cool with the lighting, but something is wrong
It just started this evening when 4 hours before operation was working normally.
do not movie it, drop it, or what not, so you don't ask, it is one my my FCP editing iMacs.
did a techtool run, found nothing, even while it was happening.
PLEASE ADVISE as if it is a loose wire, a bad video card, or what?
planning to make an appointment with the genius bar for friday.

HI,
Boot from your install disc and run the Apple Hardware Test, instructions here.
http://support.apple.com/kb/ht1509
And About the Apple Hardware Test
Make a Genius Bar reservation here.
Carolyn

Bondi iMac shuts down immediately after startup button light turns green

Is my Bondi blue baby (purchased at the midnight launch of the original iMac) finally dead?
When I push the startup button, it glows amber and the startup chime sounds. A few seconds later, the button glows green for an instant, and the power shuts off. The button then won't do anything unless I unplug the power supply for a few minutes and plug it back in.
I have tried using a paper clip to push the reset button, but to no avail. Also tried zapping the PRAM, as well as starting from a CD, but neither helped.
I know the unit has little value other than the sentimental, but my mother-in-law (who inherited it from me) is used to it and is hoping that I can bring it back to life.
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Hey H S,
This is from the service manual for the Bondi:
"The battery on the logic board controls the stored system settings,
such as date and time. It is important to note that the battery does
not affect power at startup."
However this is from page 11 of the s. manual for the 400, SE and DV:
"7 Press the power on button on the front of the computer again.
If the computer won’t start, go to the next step. If the
computer does start, you may have a *bad battery*."
So I always check the battery. Altho' all the won't start cases I've seen where the battery was the cause did not exibit the starts up and shuts down symptom.
Also from the manual:
"Resetting the logic board can resolve many system problems (see
the Symptom/Cure tables for examples). Whenever you have a
unit that fails to power up, you should follow this procedure
before replacing any modules.
1. Unplug the computer.
2. Disconnect the cable that runs from the power supply to the
power filter board on the bottom side of the logic board/mass
storage chassis.
3. Press the Power On button on the front of the unit.
4. Remove the logic board/mass storage chassis from the unit.
5. Remove the battery from the logic board.
6. Wait at least 10 minutes before replacing the battery.
7. Make sure the battery is installed in the correct +/-
direction.
8. Reassemble the computer and test the unit."
There are protection circuits in the iMac and usually a bad PAV ( flyback and HV caps in particular) are the cause of this particular failure symptom.
Richard
Message was edited by: spudnuty

My imac screen is flashing after startup?

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