How do I find out what is causing a random black screen on iMac?

Hello I get random black screen on a iMac and I haven't made any hardware changes. How can I find out what is causing this?
Thanks
Jer
iMac 2.66 core 2 duo with Snow Leopard 10.6.8

You can do an SMC and PRAM reset. These won't hurt anything and 'might,' maybe help the screen issue. If it doesn't, then take it into an Apple store or AASP for their guidance and advance testing diagnostics.
SMC:
Shut down the computer.
Unplug the computer's power cord.
Wait fifteen seconds.
Attach the computer's power cord.
Wait five seconds, then press the power button to turn on the computer.
PRAM:
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.

Similar Messages

I have recently got a new replacement iPhone 4. since I got this I have found that my data allowance is getting used up during the night while my phone is charging on the bedside table. How an I find out what is causing this and stop it happening

I have recently got a new replacement iPhone 4. Since I got this I have found that my data allowance is getting used up during the night while my phone is charging on the bedside table. How an I find out what is causing this and stop it happening? Some nights the usage is 150 meg!

You can not access the backup directly.
Did you restore your replacement from this backup?
If so then you already have everything in the backup on your device.
If not, you can wipe the device and restore from this backup:
Settings > General > Reset > Erase All Content & Settings
What is it you are worried about losing that isn't already on your current device?

How do I find out what the latest software installation is on my iMac?

Usually "install updates now" windows indicate what you are installing or updating. If that information is not included how do you find out what it is that you installed?

Which OS? The latest versions don't have a Software Update prefPane. To view what's installed with those, you need to run the System Information.app located in /Applications/Utilities/ and click on the Installations item.

My MacBook Pro is running very slow. How do I find out what is causing this?

How do I find out why my MacBook Pro is running so slow? Then how do I fix it?

Suggestions of Things You Can Do To Help A Slow Computer
If your computer seems to be running slower here are some things you can do:
Start with visits to:     OS X Maintenance - MacAttorney;
                                  The X Lab: The X-FAQs;
                                  The Safe Mac » Mac Performance Guide;
                                  The Safe Mac » The myth of the dirty Mac;
                                  Mac maintenance Quick Assist.
Boot into Safe Mode then repair your hard drive and permissions:
Repair the Hard Drive and Permissions Pre-Lion
Boot from your OS X 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.
Repair the Hard Drive - Lion/Mountain Lion/Mavericks
Boot to the Recovery HD:
Restart the computer and after the chime press and hold down the COMMAND and R keys until the Utilites 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 disk icon and click on the arrow button below.
When the recovery menu appears select Disk Utility. 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, then click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu. Select Restart from the Apple menu.
Restart your computer normally and see if this has helped any. Next do some maintenance:
For situations Disk Utility cannot handle the best third-party utility is Disk Warrior; DW only fixes problems with the disk directory, but most disk problems are caused by directory corruption; Disk Warrior 4.x is now Intel Mac compatible.
Note: Alsoft ships DW on a bootable DVD that will startup Macs running Snow Leopard or earlier. It cannot start Macs that came with Lion or later pre-installed, however, DW will work on those models.
Suggestions for OS X Maintenance
OS X performs certain maintenance functions that are scheduled to occur on a daily, weekly, or monthly period. The maintenance scripts run in the early AM only if the computer is turned on 24/7 (no sleep.) If this isn't the case, then an excellent solution is to download and install a shareware utility such as Macaroni, JAW PseudoAnacron, or Anacron that will automate the maintenance activity regardless of whether the computer is turned off or asleep. Dependence upon third-party utilities to run the periodic maintenance scripts was significantly reduced since Tiger. These utilities have limited or no functionality with Snow Leopard or later and should not be installed.
OS X automatically defragments files less than 20 MBs in size, so unless you have a disk full of very large files there's little need for defragmenting the hard drive.
Helpful Links Regarding Malware Protection
An excellent link to read is Tom Reed's Mac Malware Guide.
Also, visit The XLab FAQs and read Detecting and avoiding malware and spyware.
See these Apple articles:
          Mac OS X Snow Leopard and malware detection
          OS X Lion- Protect your Mac from malware
          OS X Mountain Lion- Protect your Mac from malware
          About file quarantine in OS X
If you require anti-virus protection I recommend using VirusBarrier Express 1.1.6 or Dr.Web Light both from the App Store. They're both free, and since they're from the App Store, they won't destabilize the system. (Thank you to Thomas Reed for these recommendations.)
Troubleshooting Applications
I recommend downloading a utility such as TinkerTool System, OnyX, Mavericks Cache Cleaner, or Cocktail that you can use for removing old log files and archives, clearing caches, etc. Corrupted cache, log, or temporary files can cause application or OS X crashes as well as kernel panics.
If you have Snow Leopard or Leopard, then for similar repairs install the freeware utility Applejack. If you cannot start up in OS X, you may be able to start in single-user mode from which you can run Applejack to do a whole set of repair and maintenance routines from the command line. Note that AppleJack 1.5 is required for Leopard. AppleJack 1.6 is compatible with Snow Leopard. Applejack does not work with Lion and later.
Basic Backup
For some people Time Machine will be more than adequate. Time Machine is part of OS X. There are two components:
1. A Time Machine preferences panel as part of System Preferences;
2. A Time Machine application located in the Applications folder. It is
    used to manage backups and to restore backups. Time Machine
    requires a backup drive that is at least twice the capacity of the
    drive being backed up.
Alternatively, get an external drive at least equal in size to the internal hard drive and make (and maintain) a bootable clone/backup. You can make a bootable clone using the Restore option of Disk Utility. You can also make and maintain clones with good backup software. My personal recommendations are (order is not significant):
1. Carbon Copy Cloner
2. Get Backup
3. Deja Vu
4. SuperDuper!
5. Synk Pro
6. Tri-Backup
Visit The XLab FAQs and read the FAQ on backup and restore. Also read How to Back Up and Restore Your Files. For help with using Time Machine visit Pondini's Time Machine FAQ for help with all things Time Machine.
Referenced software can be found at MacUpdate.
Additional Hints
Be sure you have an adequate amount of RAM installed for the number of applications you run concurrently. Be sure you leave a minimum of 10% of the hard drive's capacity as free space.
Add more RAM. If your computer has less than 2 GBs of RAM and you are using OS X Leopard or later, then you can do with more RAM. Snow Leopard and Lion work much better with 4 GBs of RAM than their system minimums. The more concurrent applications you tend to use the more RAM you should have.
Always maintain at least 15 GBs or 10% of your hard drive's capacity as free space, whichever is greater. OS X is frequently accessing your hard drive, so providing adequate free space will keep things from slowing down.
Check for applications that may be hogging the CPU:
Pre-Mavericks
Open Activity Monitor in the Utilities folder. Select All Processes from the Processes dropdown menu. Click twice on the CPU% column header to display in descending order. If you find a process using a large amount of CPU time (>=70,) then select the process and click on the Quit icon in the toolbar. Click on the Force Quit button to kill the process. See if that helps. Be sure to note the name of the runaway process so you can track down the cause of the problem.
Mavericks and later
Open Activity Monitor in the Utilities folder. Select All Processes from the View menu. Click on the CPU tab in the toolbar. Click twice on the CPU% column header to display in descending order. If you find a process using a large amount of CPU time (>=70,) then select the process and click on the Quit icon in the toolbar. Click on the Force Quit button to kill the process. See if that helps. Be sure to note the name of the runaway process so you can track down the cause of the problem.
Often this problem occurs because of a corrupted cache or preferences file or an attempt to write to a corrupted log file.

Incorrect IP displayed, but can connect to the Internet. How can I find out what's causing this?

I'm running 10.6.8, and various programs and websites that report my IP address are not displaying the correct one. I'm operating with a static IP, and I know my AirPort's IP, and the one displayed is neither of those (and in fact cannot be given out by my airport).
I can still connect to the Internet, but some services which require people to connect to my IP fail because the program on my end is hosting at the wrong IP.
Is there any way to find out where this rogue IP came from and eliminate it?
Of note, my AirPort is my only active network protocol (all others are disabled), and about 10% of the time, a restart manages to fix the problem until the next time I boot up my computer, without me changing any other settings.

When you use the Internet, you need to have a registered IP address. This is provided by your ISP, and you have assigned it to your Router.
You then get a "private" IP Address from your Router via DHCP which, by definition, is not visible or reachable on the Internet, in one of these ranges:
192.168.xxx.yyy
172.xxx.yyy.zzz
10.xxx.yyy.zzz
Your Router acts as your agent on the Internet, and bad guys cannot send you... anything you do not have your Router ask for, as you are invisible.

How can I find out what is causing this error in SQL Developer Data Modeler

Friends,
I am trying to import entities into into SQL Developer Data Modeler from Oracle Designer 10.1.2.3.
In case of need I perform these steps to perform the import:
File --> Import --> Oracle Designer Model --> Select database connection --> Select work area --> select application system --> select one entity --> Click finish --> Import starts
During the import process I see an alert dialog box with the message:
There are errors in import - check Log file Clicking Ok dismisses the alert box and I see the following summary screen:
Oracle SQL Developer Data Modeler Version: 2.0.0 Build: 584
Oracle SQL Developer Data Modeler Import Log
Date and Time: 2010-08-09 14:27:26
Design Name: erdtest
RDBMS: Oracle Database 10g
          All Statements:           32
          Imported Statements:      32
          Failed Statements:           0
          Not Recognized Statements:      0The Entity is then displayed in the Logical View within SQL Developer Data Modeler.
Upon checking the log file I see the following entry:
2010-08-09 13:50:34,025 [Thread-11] ERROR ODExtractionHandler - Error during import from Designer Repository
java.lang.NullPointerException
     at oracle.dbtools.crest.imports.oracledesigner.logical.ODORelation.createArcs(Unknown Source)
     at oracle.dbtools.crest.imports.oracledesigner.logical.ODORelation.generate(Unknown Source)
     at oracle.dbtools.crest.imports.oracledesigner.ODExtractionHandler.generateDesign(Unknown Source)
     at oracle.dbtools.crest.imports.oracledesigner.ODExtractionController$Runner.run(Unknown Source)
     at java.lang.Thread.run(Thread.java:619)Can anyone shed any light on this error?
Thanks in advance for any help you may be able to provide.

No this helps a lot. It's not strange. Firstly, in a versioned repository you should see Private Workareas and Shared workareas, so your workarea may be in either of these. It won't be in the Global Shared Workarea, as this only for non-versioned repositories. (I like to open the RON by selecting the full Repository, that way I can see the private and shared worlareas and the configuration and containers all in the same tree.
Now your workarea is defined by a set of rules, so when you expand the workarea in the RON, and select the object, then that's the workarea and object you'll see in the import dialog in the Data Modeler. So if you check it out and check it back in, and can't see it in the RON, then the rule is not seeing this object. (Did you refresh the workarea in the RON?) If you can't see it in the RON, you can't see it in the Data Modeler. If you're working in a versioned repository, you need to work in the specific work area, i.e V27 and this is what you need to select in the Data Modeler.
It looks like you are selecting the wrong workarea in the Data Modeler.
Sue

How can i find out what or why mac is running so slow ?

My Mac is running as slow as a week in jail , how can i find out what is causing it , I have 1TB memory , using 635 of it at the moment. i'm using version 10.7.1 , lion. It just seems so slow to respond to anything , start up , open an app , go from one song to another in iTunes , go from one event to another in iPhoto , everything is slow . any ideas out there folks ? I'd appreciate the help.
Thanks .

Here is all the information i can muster , I still can't find RAM .
Processor 3.2 GHz Intel Core i3
Memory 4 GB 1333 MHz DDR3
Graphics ATI Radeon HD 5670 512 MB
Software Mac OS X Lion 10.7.1 (11B26)

How to find out what is causing an error in a BPM process

I have a very basic question and I can't figure it out from help.sap.com
I have a BPM process deployed to a SAP NW Java BPM 7.40 system. It can be triggered with a web service call.
It goes into error immediately. I go to NW Administrator > Operations > Process and Tasks > Manage Processes and see the process with status "Error". But the "Error log" tab below is grayed out. I can't see any error message anywhere.
How do I find out what is wrong?

Ah, I didn't notice that on the history tab I can switch from Basic to Medium or Advanced, in Basic it was showing nothing. In Medium and Advanced it shows:
Mapping failed
com.sap.engine.services.jndi.persistent.exceptions720.NameNotFoundException: Object not found in lookup of test.sap.com.polreuse.ejbs.UUIDProviderLocal.
java.lang.IllegalArgumentException: Could not lookup 'test.sap.com/bpmear/LOCAL/UUIDProvider/test.sap.com.polreuse.ejbs.UUIDProviderLocal' bean
com.sap.mapping.lib.execution.api.exception.TExecutionException
at EJB::test.sap.com/bpmear/LOCAL/UUIDProvider/test.sap.com.polreuse.ejbs.UUIDProviderLocal( StandardInvocation:invoker )
at ( DeepExpression )
at UUID( TerminalPart:expression )
at result( BroadPart:child )
at ( NarrowMapping )
at com.sap.mapping.lib.execution.implementation.Compiler$StandardMappingFunction@241ade69( StandardInvocation:invoker )
at ( DeepExpression )
at MessageHeader( TerminalPart:expression )
at http://sap.com/xi/SAPGlobal20/Global:NewLBrdngFSCreateRequest( BroadPart:child )
at ( NarrowMapping )
What could this mean? I didn't deploy all parts correctly or something like that?
Also, where do I check the default trace?

When a vi hangs...how do I find out what it is waiting for?

I have a vi. It is "waiting for front panel activity". I cause some front panel activity by pressing a control...and the vi functions. I then press the same button again and the vi hangs, the front panel does not respond to any mouse activity. When I run the highlight execution function it shows that the case controled by the value change of the control executes to the end in the true case, but then there is no further action anywhere on (in) the vi.
How do you find out what the vi is waiting on to proceed, or which element "has the ball" so to speak.
Thanks
Stopped Humming for a while.

If you have event structures, you usually have no longer any need for "wait for front panel activity". This was more of a cheap bandaid solution before the introduction of the event structure.
Many front panel operation don't need to trigger any events or do anything, so spinning the "wait for activity loop" everytime something is clicked is a total waste of resources.
You should create events only for things that really do something while other controls (e.g. configuration) don't need to be serviced by any event. The control will keep the data until it is needed by the code.
Here is an example:
You need to set aquisition parameters (rate, # of points, etc.) then press a button to start acquisition. None of the paramter settings need any events or need to spin any loops. Once start is pressed, their last settings will get read from the terminal anyway if the code is layed out correctly. And so on....
LabVIEW Champion . Do more with less code and in less time .

My MacBook Pro isn't a year old yet and would like to use iCloud. However, very apprehensive about Lion upgrade...how can I find out what I will lose if I upgrade?

My MacBook Pro isn't a year old yet and would like to use iCloud. However, very apprehensive about Lion upgrade...how can I find out what I will lose if I upgrade?

Ajimd33 wrote:
I appreciate the prompt response. Having read several threads, you can appreciate why I would be hesistant to upgrade to the Lion. All I basically use is Office for Mac and the other basic functions such as email/calendar/address/contacts...etc. I have read horror stories about peoples stuff dissapearing into cyberspace and obvi dont want that to happen.
That's all nonsense. Most people don't post anything if they don't have any problems. People who do have problems usually have very specific reasons for them that they have caused themselves.

How do I find out what applications are running in the background

I have a 2008 iMac with 2GB memory. How do I find out what programs are running in the background? I am going to buy a new iMac before the end of the year to replace this one. When I looked at Activity Monitor it shows 1.8Gb used but doesn't tell all the programs running.

open activity monitor [if it doesnt launch click winders>Activity Monitor]. then it'll show all proceses

I do not know my apple administrator username and password? How do I find out what it is? I am trying to download IBM Notes and Domino onto my MacBook Pro and I cannot download the software without verifying my apple administrator username/password

I do not know my apple administrator username and password. How do I find out what it is? I am trying to download IBM Notes and Domino onto my MacBook Pro and I cannot download the software without verifying my apple administrator username and password.

iOS is only for mobile devices, so:
Resetting or changing a password:
For Snow Leopard or earlier: http://support.apple.com/kb/HT1274
For Lion or later: http://support.apple.com/kb/HT6022
For Mavericks users:
http://www.macworld.co.uk/how-to/mac-software/how-change-admin-password-mac-3535 328/
This is also useful:
http://www.macworld.co.uk/ipad-iphone/news/?newsid=3463233&olo=email
If it's running Mac OS X 10.6.8 or earlier, insert a Mac OS X install DVD, restart with the Option key held down, click on it, and use the Reset Password utility.
If it's running Mac OS X 10.7 or newer, restart with the Command and R keys held down, open the Terminal, and use the resetpassword command:
https://discussions.apple.com/docs/DOC-4101

How do I find out what my PW is on my Mac or at least how to reset it?

I reset my password for internet site but i must have a different pw on my Mac, it will not let me do updates without it* The PW hint in the sign in screen is not working. How do I find out what my PW is on my Mac or at least how to reset it?
thanks,
sticksrrll.

Sounds like you want your administrative password on the Mac so can install? For starters, you'll want to ask in a Mac forum. I know you used to be able to reset it using the install disk but haven't tried that for years.

I seem to not enter the correct answers to my security questions for itunes to buy an in-app purchase and also cannot answer the questions exactly like i answered them when creating the account for my ipod, how do i find out what answers i put

I seem to not enter the correct answers to my security questions for itunes to buy an in-app purchase and also cannot answer the questions exactly like i answered them when creating the account for my ipod, how do i find out what answers i put for my ipod touch and itunes?

Try these previous discusssions:
recover answers to security questions: Apple Support Communities
how do i change apple ID security...: Apple Support Communities

How do i find out what devices are authorised on my apple ID?

I have just bought a new iMac and want to get all my itunes library etc on it. However, apparently i have reached my limit of 5 authorisations, which is entirely possible as I have had a number of iphones, Macair and ipads, some of which I either no longer own or are no longer functioning. How do I find out what devices are authorised and then deauthorise any that I don't use any more - given that they may not even work!

Welcome to the Apple Community.
You can't de-authorise just the computers you no longer have access to.
Your only option is to de-authorise all your computers and then re-authorise those you wish to be authorised. You can do this by logging into your account settings in iTunes on your computer (Store > View My ID) and selecting the option to de-authorise all.
Please note however, you are only permitted to do this once in each 12 month period, therefore you would be better de-authorising your computers before you lose access to them. you can do this from the 'Store' menu in iTunes.

How do I find out what is causing a random black screen on iMac?

Similar Messages

Maybe you are looking for