White screen following system update

[ashleykaryl]

I have an old 2007 iMac that I keep as a backup machine and it was working fine earlier this evening running El Capitan. I noticed in the App Store that there was a recommended Apple security update, so I ran that and since then all I've had a white screen at startup.

I've tried the following without success

1) Resetting the SMC
2) Resetting NVRAM
3) Starting in Safe mode
4) Attempted entering recovery mode
5) Restarted in verbose mode
6) Unplugged peripherals

Nothing seems to make a bit of difference here and while there is an immediate chime at startup, nothing appears beyond the white screen. Any ideas how this could be resolved, because it seems like too much of a coincidence for a hardware failure immediately following a system security update.

 

[Samuelsan2001]

I have an old 2007 iMac that I keep as a backup machine and it was working fine earlier this evening running El Capitan. I noticed in the App Store that there was a recommended Apple security update, so I ran that and since then all I've had a white screen at startup.

I've tried the following without success

1) Resetting the SMC
2) Resetting NVRAM
3) Starting in Safe mode
4) Attempted entering recovery mode
5) Restarted in verbose mode
6) Unplugged peripherals

Nothing seems to make a bit of difference here and while there is an immediate chime at startup, nothing appears beyond the white screen. Any ideas how this could be resolved, because it seems like too much of a coincidence for a hardware failure immediately following a system security update.

Hardware issues often show up during updates they change a lot of things and put the computer under strain and your machine is pushing 11 years old that’s brilliant for any computer, but it’s getting to the stage where a logic board failure is to be expected at any time.

I would suggest you try booting from an external drive maybe with an external screen to check it’s not just the lcd that’s died.

 

[ashleykaryl]

That's a good idea. I'll try that.

This particular computer doesn't have a backup and it won't run anything more modern than El Capitan, but I'll try to work something out, even it means clean installing El Capitan on a different drive. The Mac Pro is running High Sierra on APFS, so I don't think it would even be viable to try starting the iMac in target mode.
[doublepost=1515410353][/doublepost]If I press the D key to run a hardware test I see a question mark inside a folder that flashes for about 30 seconds and then reverts to white for a while and this continues in a cycle. That would indicate difficulty finding the boot volume, though I suppose there could be various reasons for that and I haven't managed to go beyond that point at this stage.

One thing I'm actually wondering about is how to safely dispose of an iMac given that it still has current information on the hard drive, which I cannot easily access.

 

[Samuelsan2001]

That's a good idea. I'll try that.

This particular computer doesn't have a backup and it won't run anything more modern than El Capitan, but I'll try to work something out, even it means clean installing El Capitan on a different drive. The Mac Pro is running High Sierra on APFS, so I don't think it would even be viable to try starting the iMac in target mode.
[doublepost=1515410353][/doublepost]If I press the D key to run a hardware test I see a question mark inside a folder that flashes for about 30 seconds and then reverts to white for a while and this continues in a cycle. That would indicate difficulty finding the boot volume, though I suppose there could be various reasons for that and I haven't managed to go beyond that point at this stage.

One thing I'm actually wondering about is how to safely dispose of an iMac given that it still has current information on the hard drive, which I cannot easily access.

Well it does sound like a dead drive there and an ssd may well transform your usage of the machine. If it boots from an external drive then it will almost undoubtedly just need a new hard drive or new SATA cable (but use an ssd it makes a massive difference). If it is anything else it’s probably just not worth the time money and effort to fix.

Hard drive replacement guides

https://www.ifixit.com/Guide/iMac+Intel+20-Inch+EMC+2133+and+2210+Hard+Drive+Replacement/1008

https://www.ifixit.com/Guide/iMac+Intel+24-Inch+EMC+2134+and+2211+Hard+Drive+Replacement/8968

As for getting rid of it if needed just open it up take out the hard drive and sell it for parts should get at least $100.

 

[ashleykaryl]

I use an PCI based SSD on my Mac Pro, which originally came with a SATA drive. The SSD transformed the performance and even low end machines appear pretty snappy with an SSD.

Given the age of the iMac, I don't think it's worth spending any money here, because anything major could go wrong at the drop of a hat. Last month the logic board died on my daughter's three month old 2017 MacBook Pro, so these things do happen.

 

[ashleykaryl]

It's not even starting properly from an external drive with a clean install of El Capitan. Just white screen and nothing else, so I'm guessing logic board.