27" iMac doesn't boot past white screen, not-responsive

Using the COMMAND-OPTION keys on the RIGHT side of the keyboard is imperative else this method will not work. It took me ages to find this solution on the Web.

John - Love your exuberance in answering questions, only problem here is this is a very old question and has long since been answered with the correct answer - Accepted Answer. Look for ones that don't haven any answers. Hope to see more postings!

John, have an iMac and had the white deadly screen yesterday. I tried all sorts of ways to resolve the issue.

I was able to restart the computer on SAFE MODE, but, if i try to log on my computer through the main admin the screen will flash once and it prompts me to type in my password.

Since i have guest user on my PC i was able to login using that account just fine.

What can i do from here in order to recover my main access to my computer and files using my main admin access?

Thanks to all your helps!

Alex P

Where do you get a Boot CD?

Should have come with the Mac. If not friends, or hunt online for a d/l.

This worked for me! It had me puzzled for days! Kept swapping in new drives and they worked for a day then boom back to the same problem!

The 1st problem was it wasnt booting and kept going to a white screen, then I tried to boot from an external and I got a blue screen. Reloaded software on using thunderbolt and I rebooted with the same problem but it was going into a loop of boot, apple logo, loading line, white screen and reboot.

I rebooted holding D and it fixed it! Thankyou

Not really sure what holding the D on start up does, but it worked for me also. I been having problems starting my iMac, keep getting the white screen with the Apple logo. If I play with it long enough, eventually it will start up. At one point, I got a black screen with some messages that said something about bad memory, I showed it to the tech person at work, and he suggested I try to replace the memory cards, which I did. Still got the white screen after replacement. Finally came across this post and gave it a try, and it started up. Don't know if it'll continue to work as I'm afraid to shut it down right now, but it did work for now! Thanks!

Hi:

Your iMac still works? Mine can't get pass the white Screen. Pressing down D starts some Hardware Test over Internet. Unfortunately after finish, the white screen shows again after Reboot.

Red 5.

Thanks for this! I am not good at this stuff, but the D key boot ran the diagnostics, and it reported the hardware was fine. Then it booted up fine on restart. Couldn't believe something finally worked.

This is a bit weird! :)

Though it just runs a test which should change nothing in the machine, it worked for me too! I noticed that the computer got quite hot during the extended test; I wonder if this created a kind of reflow of the graphic card... :-D

Edit:

Well... it worked for 2 restarts... :-/

Now the extended hardware test neither finds a problem nor makes the iMac starting again. I still have a little hope that it is the hard disk, but it looks pretty much like the graphic card... -__-

Thanks for the quick response. I've tried to boot from a Mountain Lion Install USB drive, but that too doesn't get past the white screen. I will try using the Target Mode and see if I can run Disk Utility through another machine.

That should do it! Also why don't you copy off your important stuff first just to be safe here.

Aza - We've given up trying to salvage graphic boards as while you maybe able to get it working it won't last, sorry ;-{ We did 5 systems and all five ended up dead in a matter of weeks. Best to just bite the bullet here and replace the card with a new unit. Besides, given the amount of work just to get it out its just not with doing it over and over again.

I tried the above also Jay, but different, i try the command+s . o problem loads of white scripted code and text then, i try fsck-fy no joy did nothing, so thought what the !&&*, i'll just reboot then by typing that in, and then it flashed did something upon loading and now i got it back online again, only i am going to try to delete the partition and refresh the os x instead obviously corrupted or something, then i will buy 32gn ram and upgrade memory and change the drive from a simple one to a 1tb ssd drive sorted, will update as and when i get this done....

Thanks for the info though :-)

Hi there, I have a second hand iMac 27" but don't have any other data than that, I bought it from a company that went bust. I now have the white screen of death. Is there any way I can discover if my iMac is one of the 'problem' iMac's covered by the recall?

If you look at the bottom of the foot stand you'll find the serial number with it you can find out what year your system was made and what options it has but plugging in the serial number into this web site: EveryMac then review the Apple T/N link above HT203787 is it the same graphics card? If so make an appointment with the Apple Store to have it fixed under the extended warranty. Even if it isn't under extended warranty I would still bring it in Apple tends to have other recalls that are not documented that might be your issue here as well.

Any update on this one? I'm in the same boat now and think it's the video board (although it could be the logic board.) Since there is a known issue with the AMD (ATI) GPUs, that's my guess. I'll probably order one (new) and with the 512MB onboard vs. the 1GB or 2GB as they run hot and would likely be more prone to failing again...

I replaced with the 512MB video board and all is well. My old video card would completely pass during ASD testing, but would not boot to login screen (only half way through progress bar then black/grey screen.) Took quite a while to diagnose. Not very hard to open up this system once you've walked through it a few times.

Hi didier, have you found a solutions for this problem. i have exact same problem with my iMac EMC 2546, LATE 2012 model, I did all you mentioned, and nothing fixed the problem. please share your solutions if you have any.

Hi.

No, the only local apple approved retailer declared the whole motherboard to be defective and to be changed, obviously for a small fortune. And since at the same time I also had a deadly issue with the internal hard drive (supposedly under warranty), all this with the data recovery which they wanted to farm out and the exceedingly expensive drive swap cost, what they were asking to repair that thing was more than buying a new one. Classic apple behavior. They're bandits!!

So I got back my machine as it was and got myself an other from ebay for far less than the cost they wanted to charge me and I worked my way through getting my own data, and put this all back together with a new drive from ebay, which also cost a small fraction of what they wanted.

Basically, I didn't pay them anything more than the estimate, since they wouldn't release my machine to me without charging something.

I kept that machine, just in case I can fit it somehow.

I'm quite certain this issue, which many have encountered, could be much more easily fixed, and for far cheaper than what apple wants to charge for this.

It's quite typical apple, to charge a huge amount for something minor, so they can just scrap the old and sell a brand new one, or make a killing on the fix. Either way, they always win and cash in like bandits. NOT GOOD!!!