How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Richard Your Own Question

Richard
Richard, Apple Software Engineer
Category: Mac
Satisfied Customers: 31306
Experience:  IT Engineer for over 15 years
32989067
Type Your Mac Question Here...
Richard is online now
A new question is answered every 9 seconds

I have a iMac (27-inch, Late 2009). At power up I see the

Customer Question

I have a iMac (27-inch, Late 2009). At power up I see the white screen with an apple and the progress bar. After the progress bar is "complete" it then goes completely black. Can not see any hint of a display when looking up close. I have read some other Questions on the site (ie Command+Option+P+R ) with no luck
I have a new iMac now but hate to see this one go to waste.
Any quick thoughts as to what it is? Basically, cheap fix or $$$
Submitted: 2 months ago.
Category: Mac
Expert:  Richard replied 2 months ago.

Hi there and welcome

Can you power off the Mac

then hold the SHIFT key and with it held, power on the Mac until you get to the sign in screen and then release it.

Tell me if you can then get to this please.

Customer: replied 2 months ago.
I tried that. This time the screen went black midway thru the progress bar
Expert:  Richard replied 2 months ago.

Thanks

can you power it off.

Then remove all cables except the power cable.

Power it on and tell me please what then happens.

Customer: replied 2 months ago.
I have no cables attached except keyboard and wireless mouse.
Not sure how you'd connect remotely
Expert:  Richard replied 2 months ago.

ok, then it is not this.

Power off the wifi router then try to start it please.

Tell me if it then starts (after enabling the router and getting internet again)

Customer: replied 2 months ago.
same thing. Starts out white and goes black
Expert:  Richard replied 2 months ago.

ok, I know you tried this already but repeat the procedure another 2 times please

  1. Shut down your Mac.
  2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R.
  3. Turn on your Mac.
  4. Press and hold the Command-Option-P-R keys immediately after you hear the startup sound.
  5. Hold these keys until the computer restarts and you hear the startup sound for a second time.
  6. Release the keys.

After two times tell me if it then starts please

Customer: replied 2 months ago.
I never get the "tah dah" start up sound. When I power it on it starts white with the apple and progress bar. I hear the HDD spinning and it goes blank before I see the finish of the progress bar. Then, it sits quiet and dark. the volume is "up".
Customer: replied 2 months ago.
Seems to be blanking out sooner as if the temperature has something to do with it. The more I try things the sooner it blanks out.
Expert:  Richard replied 2 months ago.

ok, can you attempt this please

Power off the mac

Then start the Mac and hold down the Command and R keys at startup.

Hold these keys until the Apple logo appears. After your computer finishes starting up, you should see a desktop with an OS X menu bar and an OS X Utilities window

choose Disk Utility from the Utilities window, or from the Installer menu if you're started from an installation disc.

Click the First Aid tab.

Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.

Select your Startup Disk (usually named "Macintosh HD").

Click Repair. Disk Utility checks and repairs the disk.

Let this complete and when it has, tell me if you still have the problem please.

Customer: replied 2 months ago.
It goes blank almost immediately after the apple logo shows up. There is no way it makes it to the OS X menu.
I think were going down a dead end path. Perhaps the graphic/video card is shot
Expert:  Richard replied 2 months ago.

Thanks, ***** ***** confirmed the issue

It is the motherboard that has faulted. As it goes blank it points to the onboard power supply or voltage regulator. A bad video card would still leave it running but with a blank screen

I am really sorry about this and you are going to have to return the Mac to have this replaced. It will be covered by the warranty if this has not expired, and the replacement will be done at no cost to you.

I am really sorry about this, and if you have problems, or would like any additional information or assistance, please do not hesitate to let me know.

And if you can take a second to rate my service by clicking one of the stars at the top of the page, then submit, that would be greatly appreciated.

Thank you

Customer: replied 2 months ago.
A bad video card would leave what still running? The computer is still running (I can hear it), but the display is "gone". The machine does not power off.
Expert:  Richard replied 2 months ago.

Ok, I thought when you said it went off that it was powering off. In this event if it is still running it can be the video card (which is onboard) or the chipset when it tries to initialize the devices. But both are part of the motherboard and still requires this to be replaced.

Expert:  Richard replied 2 months ago.

If you would like any additional information or assistance, please do not hesitate to let me know.

Else if you can take a second to rate my service by clicking one of the stars at the top of the screen then submit, that would be greatly appreciated.

Thank you

Customer: replied 2 months ago.
the motherboard and the graphic board are one unit? Also, what is a chipset?
Expert:  Richard replied 2 months ago.

No, the motherboard is a board that holds all the components and the graphics and chipset along with the Bios, Sata ports are on this board.

Then rest of the components connect to it eg: Hard Disk

Expert:  Richard replied 2 months ago.

ok.. I wont ask about the rating again. We are only compensated when you do a positive rating, but I asked a few times and it appears this wont happen.

Fair enough, that's your choice of course. You have the information you need

All the best