Early 2006 iMac freezing

[sean101v]

Hi,

So I got a free Early 2006 iMac with a Core Duo, 2GB RAM, and a 160GB HD. After I tried (and succeeded) to remove the firmware password and install OS X 10.6.8, now I’m having a new problem. After a completely fresh install of SL, the computer boots (fairly quickly for its age) and gets to the desktop, but everything will be completely frozen (except the mouse). After waiting about 10-20 minutes, the computer finally starts to work again. Occasionally on boot up the computer will just show a blue screen for 10-20 minutes with no mouse instead.

The next problem is sleeping. When the computer goes to sleep at any point, you will not be able to wake it. The sleep LED will be on but pressing the power button/moving the mouse will do nothing to it. AFAIK it won’t wake from sleep at all, it may just take 10-20 minutes but I haven’t tested that yet.

When in safe mode, it works fine, no waiting. I also did a HDD test and all is well there. So what could it be?

Follow up question: I want to upgrade the CPU. It’s currently a 1.83GHz Core Duo (Not Core 2 Duo, a CORE Duo, really old). What processor is supported in an early 2006 17” iMac? Also, how easy is it to open? I’ve opened newer macs with the magnetic screen before, so I’m fairly skilled, I’m just hoping this’ll be easier?

 

[MistrSynistr]

Take it to a Computer Shop and get an SSD installed in it. Or Youtube it with an ifixit kit. All your problems will go away.

 

[sean101v]

Take it to a Computer Shop and get an SSD installed in it. Or Youtube it with an ifixit kit. All your problems will go away.

Hi,

I don’t think that’s the problem. The problem isn’t “the computer is slow” it’s “the computer is unusable”. Because it crashes when sleeping and freezes at boot. I did a check on the HDD and there are no problems (the HDD is healthy) so the problem is an actual problem with the computer, not just some slowness

 

[Project Alice]

Hi,

I don’t think that’s the problem. The problem isn’t “the computer is slow” it’s “the computer is unusable”. Because it crashes when sleeping and freezes at boot. I did a check on the HDD and there are no problems (the HDD is healthy) so the problem is an actual problem with the computer, not just some slowness

Hard drives can still report themselves as in good health, but not be. I'd install an SSD anyways, you can get a 120gb for like 30 bucks. Or just a new hard drive if thats what you want. Start there, and ram is the next thing. I would make a memtest usb drive and run it.

As for the CPU, I have the same iMac as you and I plan on doing the same thing. according to ifixit, it is a pain to open, but not *too* bad. It will take up to 10.8 ML with a C2D installed in it.

 

[sean101v]

Hard drives can still report themselves as in good health, but not be. I'd install an SSD anyways, you can get a 120gb for like 30 bucks. Or just a new hard drive if thats what you want. Start there, and ram is the next thing. I would make a memtest usb drive and run it.

As for the CPU, I have the same iMac as you and I plan on doing the same thing. according to ifixit, it is a pain to open, but not *too* bad. It will take up to 10.8 ML with a C2D installed in it.

A new HDD doesn’t help. Even trying to boot from the 10.6 CD (not related to HDD at all) doesn’t work. The computer keeps freezing and is unusable. There’s definitely a problem with it other than the HDD but I don’t know what. I’ve basically given up though, it was just a computer I wanted to play around with, not actually put a ton of money into. There seems to be a serious problem with it, could even be motherboard related. Thanks anyway

 

[redheeler]

Hi,

So I got a free Early 2006 iMac with a Core Duo, 2GB RAM, and a 160GB HD. After I tried (and succeeded) to remove the firmware password and install OS X 10.6.8, now I’m having a new problem. After a completely fresh install of SL, the computer boots (fairly quickly for its age) and gets to the desktop, but everything will be completely frozen (except the mouse). After waiting about 10-20 minutes, the computer finally starts to work again. Occasionally on boot up the computer will just show a blue screen for 10-20 minutes with no mouse instead.

The next problem is sleeping. When the computer goes to sleep at any point, you will not be able to wake it. The sleep LED will be on but pressing the power button/moving the mouse will do nothing to it. AFAIK it won’t wake from sleep at all, it may just take 10-20 minutes but I haven’t tested that yet.

When in safe mode, it works fine, no waiting. I also did a HDD test and all is well there. So what could it be?

Follow up question: I want to upgrade the CPU. It’s currently a 1.83GHz Core Duo (Not Core 2 Duo, a CORE Duo, really old). What processor is supported in an early 2006 17” iMac? Also, how easy is it to open? I’ve opened newer macs with the magnetic screen before, so I’m fairly skilled, I’m just hoping this’ll be easier?

Considering it works fine in Safe Mode, and you've already tried a PRAM / SMC reset, the issue is likely related to the GPU. The ATI Radeon X1600 runs hot in these models and can develop issues. It's soldered, so not much you can do aside from a complete logic board replacement.

Answer to your follow-up question: https://www.ifixit.com/Guide/iMac+Intel+20-Inch+EMC+2105+and+2118+CPU+Replacement/35350