Late 2009 iMac freezes with 10.11.5

[joscejrod]

Hello guys,

My iMac has suffered ramdon freezes the last weeks. I brought it to an Apple Store. They reinstalled the OS completely and they told me that hardware is ok. So what's the problem?
Sometimes it freezes while I'm using it, with a spinning wheel, other times, when the mac enters to sleep mode (only screen off), it's impossible to wake it up. The screen now in on, but only shows black color and a spinning wheel. All times, I have to force restart...

 

[havokalien]

graphics card probably going. failing gpu's in the iMacs are known to cause a slew of issues.

 

[MrNomNoms]

Hello guys,

My iMac has suffered ramdon freezes the last weeks. I brought it to an Apple Store. They reinstalled the OS completely and they told me that hardware is ok. So what's the problem?
Sometimes it freezes while I'm using it, with a spinning wheel, other times, when the mac enters to sleep mode (only screen off), it's impossible to wake it up. The screen now in on, but only shows black color and a spinning wheel. All times, I have to force restart...

As the person above me noted it could be the GPU but I'd also see whether it is the hard disk considering that the computer is 7 years old so I wouldn't be surprised if the hard disk is closed to dying.

 

[joscejrod]

Could it be an app that crashes the system? Maybe transmission?

 

[grahamperrin]

…

… Apple Store. They reinstalled the OS completely and they told me that hardware is ok …

How long was spent determining whether the hardware is OK? Did you leave it at the store for a few hours?

If it's a hard disk drive, and if that disk appears to be OK, then you can use the key chord for sysdiagnose to help diagnose problems involving software.

 

[joscejrod]

…

How long was spent determining whether the hardware is OK? Did you leave it at the store for a few hours?

If it's a hard disk drive, and if that disk appears to be OK, then you can use the key chord for sysdiagnose to help diagnose problems involving software.

Yes, the computer was at the apple store 2 days. They told me that they had checked the hardware completely, and all was ok. Could you explain me how to use that app? Maybe 10.11.5 has bugs?

 

[grahamperrin]

… 2 days. …

OK, if it's a hard disk drive then two days was probably long enough for a check of the media, which is more than can be done with Disk Utility.

Could you explain me how to use that app?

Begin at Preparing for the keyboard-only approach to sysdiagnose