iMac hangs

[kharisma]

Last year I did a clean install of Snow Leopard (wiped the hard drive, and started with a new OS)

I am finding that from time to time the system runs incredibly slowly for simple tasks (like selecting a different window). I have checked that I still have enough room on the hard drive (100 GB free space on a 250 GB drive). There is 4 MB RAM (no room for more). The processor is Intel Core 2 Duo 2.16 GHz.

Just lately, the system has frozen a few times, forcing me to simply turn it off and reboot. It has also been reluctant to let me log in again - I get the initial screen that lists the users, and when I click on my username, the box to allow entry of a password never appears - all the options to sleep/restart/shut down are greyed out, and it just sits there.

Eventually I do get in, but I am concerned that the day is coming when I can't get in at all.

What diagnostics or repairs can I run?
Are there any repairs I should be doing on a regular basis anyway?

 

[eljanitor]

Just sounds like a corrupted system to me. It could be from many things, it's possible that the hard drive is starting to go bad, and needs replacing. Id check the SMART status of the drive to see it its failing SMART tests. Thats the easiest thing to do. You can check that in the system profiler and just select the drive to see if it passed the last SMART test. (see picture) Also something to note is that the controller can still pass SMART testing but have an intermittent failure.


So it could be a bad controller on the drive, it could be that the motor is going bad, etc etc. It could be bad blocks on the Hard drive as well. Bad blocks don't show up under SMART testing. However there are several programs that you can purchase that check for bad blocks on hard drives.

So I'd definitely think about repairing whatever software corruption has occurred, and check it for bad blocks as well. Bad blocks usually equal replacing the drive.

A good tool to monitor your system is: iStat pro.
You can get the widget here click here

Hope this helps you.

 

[kharisma]

Thanks

I have checked the hard-drive (SMART) - it says it's ok.
The temperature of my machine is between 39-49, so that seems fine.

What about the CPU?

 

[MacHamster68]

dont rely on the smart test readings
your iMac is now near 5 years old , and if it is still the original HDD then you are lucky that it is still working at all 5 years are a long time with todays HDD technology some even start giving up after 3 years already
So do yourself and your iMac a favor change the HDD.
I mean its the cheapest part inside if you get a 250gb HDD again , but personally i would get a 500GB- 1TB HDD as those are cheap too nowadays (WD caviar black )

when you are at opening the iMac to change the harddrive give it a good clean , you will be shocked or at least surprised how much dust there is inside after 5 years

P.S.
My guess Mr.Dyson had a iMac and that gave him the idea for his cyclone bagless vacuum cleaners

 

[kharisma]

Ahh, you just said the magic words - a bigger hard-drive!! yesss!!! Hopefully that'll fix the problem.

Is there anything I ought to be doing with the Mac for maintenance? With Windows I was forever having to run the defrag.

 

[MacHamster68]

defragmentation is usually only a windows thing

Mac OS-X is pretty good at defragging its operating system on its own (unless the hard drive has filled up and forced it to write into a fragmented state) so generally we do not have to worry about defragging the System and Applications folders.

 

[kharisma]

I realise defrag is for Windows - I have had a Mac for more than 5 years now. I only cited defrag as an example of on-going maintenance - and I had to use a Windows example, because I don't know of one for the Mac.

The question is "Is there anything I ought to be doing with the Mac for maintenance?"

 

[MacHamster68]

there are tools out there , idefrag for example

onyx is another tool i like for general cleaning