Currently Being ModeratedMar 31, 2013 5:21 AM (in response to David McCourt)
If it were me - before I bother to change out the hard drive, I'd back everything up, then wipe the hard drive and do a clean install, then transfer my files back. Even though you've run utilities that say everything is OK, there may just be something out of wack that's causing the issue. I've had similar happen to me, did the clean-install and it corrected the problem.
Currently Being ModeratedMar 31, 2013 6:07 AM (in response to David McCourt)
I understand that there are some issues with the heat sensor on the drives and it is important to use the same make as the factory installed one.
AFAIK, this only started with the late 2009 models. Besides that, if it did apply to your model, it wouldn't help to use the same make drive, since those drives are Apple proprietary. If you are thinking about the OWC article about this, I don't think they got that right--and even if they did, there are no more of those compatible drives anywhere to be found.
You could work around this problem, if it does apply to your model, by getting SSD Fan Control.
However, I don't think a hard drive upgrade will make any difference for your problem. It might be more to do with indadequate RAM. Can you post a screenshot of the bottom only of the System Memory tab in Activity Monitor in Utilities. Like this
Also, switch to the CPU tab and see if anything is hogging the CPU and look in Real Memory too for any hogs.
Currently Being ModeratedApr 2, 2013 2:08 AM (in response to David McCourt)
Thanks both for your thoughts.
Dennis, yes that is a good approach but I only fairly recently upgraded to Mountain Lion with a clean intsall, so I think doing this again wouldn't help matters much.
WZZZ, yes I had read since that the heat issue is for later models.
I have the max 8GB RAM I can install in this Mac. Here is the screengrab from Activity Monitor
Nothing seems to be hogging the system much but I do run Dropbox, Google Drive and CrashPlan which do sometimes seem to slow things down.
I guess what I'd like to know is if replacing the hard drive is a good approach to get another 2 years out of this Mac.
Currently Being ModeratedApr 2, 2013 5:10 AM (in response to David McCourt)
IF the hard drive is the cause of your slow-down, changing it out will help that issue. But if the slow-down is due to something else - processor, video, mother board, etc. - it won't help. My personal experience with drives has been good - never had a hard drive failure on any of my computers in 20+years. Right now, i've got two installed in a 9-year-old Power Mac G5 and they appearing to be running as well as the day I installed them.
Currently Being ModeratedApr 2, 2013 5:29 AM (in response to David McCourt)
I don't think switching out the drive wll make any difference, although going to an SSD may, but for the capacity you want, it will be very expenseive. If the computer was at one time faster, then perhaps you're now running too many CPU or Memory intensive applications concurrently. Even though your screenshot shows no paging out and adequate RAM, you need to look at that when the slowdowns are occuring. Also enter top in Terminal and look at the figures in the parenthesis at the top of the window, which will give you a readout in real time. Also check out this tip from BobHarris about checking Memory usage.
You do need to leave a minimum of around 10GB free plus enough for future expansion (and disregard anyone who suggests you need to keep a certain percentage of disk space free); if you have that much now, the problem wouldn't be not enough drive free space.
Have a look through these articles for anything you might have missed.
One possible cause of slowdowns is some A-V program scanning always in the background. Do you have any A-V installed?
Currently Being ModeratedApr 2, 2013 7:08 AM (in response to David McCourt)
Also, CrashPlan can really slow your iMac if you have it constantly backing up your data all day long.
You should be using CrashPlan in a way where it doesn't impact your system's performance.
No matter what hard drive you buy, if you are using both backup software and have this work all day AND antivirus software, your iMac is going to run slow.
IMO, backup software should run at a time when computer activity and performance are not greatly impacted.
Like backup at night or early in the morning before the start of your work session or schedule a fixed interval of time like an hour before and after through a scheduled lunch break period. Times where your iMac's performance is not impacted greatly when you are trying to get important work done.
Currently Being ModeratedApr 3, 2013 1:41 AM (in response to David McCourt)
I do have CrashPlan running all the time so I'll change this to nightly. I'm also running Sophos AV which runs constantly but that is the default behaviour.
My main concern was the age of the drive but it seems everyone on here doesn't see that as a problem. This is different to what I've read elsewhere.
I'll make a few changes to what is running when and see how that goes. The slow downs aren't a really big problem but I was just concerned it might be indicative of the start of a drive failure.
Thanks for all your advice.