Q: How to reinstall AHT on my iMac early 2008

Thanks for the suggestions. I had tried D and option D  - the online one - and neither achieved anything. I followed the link in Mike's post to github and installed the relevant .diagnostics file in coreservices but that also made no difference. It's possible I didn't do it right of course. I've now contacted apple support who will send original discs in about a week, which I hope will work.

Many thanks for the helpful replies.

I decided to have anther go at installing the .diagnostics file from the GitHub link and whaddya know it worked. Have run the AHT and no problems detected. Time to look elsewhere. Many thanks.

I decided to have anther go at installing the .diagnostics file from the GitHub link and whammy know it worked. Have run the AHT and no problems detected. Time to look elsewhere. Many thanks.

Well, this is in fact my Dad's mac and I've been using it whilst on a extended stay with him. It's an iMac 8,1 with the original spec - so 2gb ram and a 2.66 Core 2 Duo chip, plus a 320 SATA hard drive. The OS was Leopard, upgraded to Snow Leopard, clean install, by me. A while back I partitioned the hard drive to allow me to add a more up to date OS so he could try it and see if he could adapt - he's 94 now. I tried for Mavericks, which looks very much like SL, but I just couldn't get it onto his mac. Apple seems all very Windows these days and despite my best efforts I gave up on Mavericks. So I installed Yosemite and it's too different for him as it turns out. I've not upgraded it to El Capitan as it looks as though it's not really compatible with this mac.

I've got the same problem regardless of which OS I boot into. Most programmes I open bounce in the dock for a long time. They rarely close without using force quit. Sometimes they simply don't open at all. The browsers seem to be the main problem in that after using Safari, Chrome, or Firefox for say half an hour they start to slow down and then all I get is the spinner. If I close say Safari and use Chorme then Chrome will be Ok for 20 mins or so and then jam up.

Activity monitor shows large amounts of memory being used by the browsers after a while - 1.5 of the 2 gigs. But it doesn't show an memory pressure - all green and low. My usual approach would be to add 2 gigs and see - but I'm not sure that's the problem. I have a mac mini 2014 core i5 and 4 gigs of memory which shipped with Mavericks and after a few months it ground to a halt. Apple's fixers said just reinstall the OS - not a "genius" solution as it has pretty much ground to a halt again now with El Capitan installed.

So I looked at a hardware issue first  - the AHT - and as I know very little about OSX that's as far as I've got. My assumption is that Apple concentrates on other products these days and the OS for actual computers doesn't get the care it needs. When these things have happened with windows I've usually given up and installed the relevant Linux to get the machine to run, but that's not an option here I don't think.

Thanks mike - here it is

EtreCheck version: 2.9.3 (253)

Report generated 2016-02-10 09:17:30

Download EtreCheck from http://etrecheck.com

Runtime 5:23

Performance: Below Average

Click the [Support] links for help with non-Apple products.

Click the [Details] links for more information about that line.

Problem: Computer is too slow

Hardware Information: ⓘ

    iMac (20-inch, Early 2008)

    [Technical Specifications] - [User Guide] - [Warranty & Service]

    iMac - model: iMac8,1

    1 2.66 GHz Intel Core 2 Duo CPU: 2-core

    2 GB RAM - Insufficient RAM! Upgradeable - [Instructions]

        BANK 0/DIMM0

            1 GB DDR2 SDRAM 800 MHz ok

        BANK 1/DIMM1

            1 GB DDR2 SDRAM 800 MHz ok

    Bluetooth: Old - Handoff/Airdrop2 not supported

    Wireless:  en1: 802.11 a/b/g/n

Video Information: ⓘ

    ATI Radeon HD 2600 Pro - VRAM: 256 MB

        iMac 1680 x 1050

System Software: ⓘ

    OS X Yosemite 10.10.5 (14F1605) - Time since boot: about one day

Disk Information: ⓘ

    ST3320820AS_Q disk0 : (320.07 GB) (Rotational)

        EFI (disk0s1) <not mounted> : 210 MB

        Macintosh HD (disk0s2) /Volumes/Macintosh HD : 159.86 GB (62.93 GB free)

        Macintosh HD 2 (disk0s3) / : 159.21 GB (109.79 GB free)

        Recovery HD (disk0s4) <not mounted>  [Recovery]: 650 MB

USB Information: ⓘ

    HP Deskjet D2500 series

    Apple, Inc. Keyboard Hub

        Primax Electronics Apple Optical USB Mouse

        Apple, Inc Apple Keyboard

    Apple Inc. Built-in iSight

    Apple Inc. BRCM2046 Hub

        Apple Inc. Bluetooth USB Host Controller

    Apple Computer, Inc. IR Receiver

Gatekeeper: ⓘ

    Anywhere

System Launch Agents: ⓘ

    [killed]    com.apple.CallHistoryPluginHelper.plist

    [killed]    com.apple.icloud.fmfd.plist

    [loaded]    149 Apple tasks

    [running]    61 Apple tasks

    2 processes killed due to insufficient RAM

System Launch Daemons: ⓘ

    [killed]    com.apple.ctkd.plist

    [killed]    com.apple.ifdreader.plist

    [killed]    com.apple.nehelper.plist

    [killed]    com.apple.periodic-weekly.plist

    [killed]    com.apple.tccd.system.plist

    [killed]    com.apple.wdhelper.plist

    [loaded]    177 Apple tasks

    [running]    79 Apple tasks

    6 processes killed due to insufficient RAM

Launch Daemons: ⓘ

    [loaded]    com.adobe.fpsaud.plist [Support]

    [loaded]    com.microsoft.office.licensing.helper.plist [Support]

User Launch Agents: ⓘ

    [loaded]    com.google.keystone.agent.plist [Support]

    [running]    com.spotify.webhelper.plist [Support]

User Login Items: ⓘ

    iTunesHelper    Application  (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)

    Android File Transfer Agent    Application  (~/Library/Application Support/Google/Android File Transfer/Android File Transfer Agent.app)

Other Apps: ⓘ

    [running]    com.apple.xpc.launchd.oneshot.0x10000004.EtreCheck

    [running]    com.google.android.mtpagent.6280

    [running]    com.microsoft.Outlook.137204

    [running]    com.microsoft.Word.137772

    [running]    com.microsoft.alerts.daemon.188892

    [running]    com.microsoft.autoupdate.fba.153108

    [running]    com.microsoft.outlook.databasedaemon.139476

Internet Plug-ins: ⓘ

    SharePointBrowserPlugin: Version: 14.6.0 - SDK 10.6 [Support]

    FlashPlayer-10.6: Version: 20.0.0.286 - SDK 10.6 [Support]

    QuickTime Plugin: Version: 7.7.3

    Flash Player: Version: 20.0.0.286 - SDK 10.6 Outdated! Update

    Default Browser: Version: 600 - SDK 10.10

Safari Extensions: ⓘ

    AdBlock

3rd Party Preference Panes: ⓘ

    Flash Player  [Support]

Time Machine: ⓘ

    Time Machine not configured!

Top Processes by CPU: ⓘ

         5%    WindowServer

         3%    com.apple.WebKit.WebContent(5)

         3%    mdworker(6)

         1%    kernel_task

         1%    Dock

Top Processes by Memory: ⓘ

    502 MB    com.apple.WebKit.WebContent(5)

    262 MB    kernel_task

    92 MB    Safari

    51 MB    mdworker(6)

    43 MB    Finder

Virtual Memory Information: ⓘ

    41 MB    Free RAM

    1.96 GB    Used RAM (400 MB Cached)

    49 MB    Swap Used

Diagnostics Information: ⓘ

    Feb 8, 2016, 07:27:11 PM    Self test - passed

Yes seem pretty clear. I'll reboot intoSnow Leopard and see what that produces. Thanks Mike.

Hi Mike

This is the read out from Etrecheck on Snow Leopard

treCheck version: 2.9.3 (253)

Report generated 2016-02-10 15:04:32

Download EtreCheck from http://etrecheck.com

Runtime 5:32

Performance: Below Average

Click the [Support] links for help with non-Apple products.

Click the [Details] links for more information about that line.

Problem: Computer is too slow

Hardware Information: ⓘ

    iMac (20-inch, Early 2008)

    [Technical Specifications] - [User Guide] - [Warranty & Service]

    iMac - model: iMac8,1

    1 2.66 GHz Intel Core 2 Duo CPU: 2-core

    2 GB RAM - Insufficient RAM!

        BANK 0/DIMM0

            1 GB DDR2 SDRAM 800 MHz ok

        BANK 1/DIMM1

            1 GB DDR2 SDRAM 800 MHz ok

    Bluetooth: Old - Handoff/Airdrop2 not supported

    Wireless:  en1: 802.11 a/b/g/n

Video Information: ⓘ

    ATI Radeon HD 2600 Pro - VRAM: 256 MB

        iMac 1680 x 1050

        spdisplays_display_connector

System Software: ⓘ

    OS X Snow Leopard 10.6.8 (10K549) - Time since boot: less than an hour

Disk Information: ⓘ

    ST3320820AS_Q disk0 : (298.09 GB) (Rotational)

        - (disk0s1) <not mounted> : 210 MB

        Macintosh HD (disk0s2) / : 159.86 GB (62.65 GB free)

        Macintosh HD 2 (disk0s3) /Volumes/Macintosh HD 2 : 159.21 GB (110.05 GB free)

        Recovery HD (disk0s4) <not mounted>  [Recovery]: 650 MB

USB Information: ⓘ

    Apple, Inc. Keyboard Hub

        Primax Electronics Apple Optical USB Mouse

        Apple, Inc Apple Keyboard

    HP Deskjet D2500 series

    Apple Inc. Built-in iSight

    Apple Inc. BRCM2046 Hub

        Apple Inc. Bluetooth USB Host Controller

    Apple Computer, Inc. IR Receiver

Startup Items: ⓘ

    HP IO: Path: /Library/StartupItems/HP IO

    HP Trap Monitor: Path: /Library/StartupItems/HP Trap Monitor

    Startup items are obsolete in OS X Yosemite

System Launch Agents: ⓘ

    [loaded]    64 Apple tasks

    [running]    10 Apple tasks

System Launch Daemons: ⓘ

    [loaded]    141 Apple tasks

    [running]    30 Apple tasks

Launch Agents: ⓘ

    [loaded]    com.hp.help.tocgenerator.plist [Support]

Launch Daemons: ⓘ

    [loaded]    com.adobe.fpsaud.plist [Support]

    [loaded]    com.microsoft.office.licensing.helper.plist [Support]

User Launch Agents: ⓘ

    [loaded]    com.adobe.ARM.[...].plist [Support]

    [loaded]    com.bittorrent.uTorrent.plist [Support]

    [loaded]    com.google.keystone.agent.plist [Support]

    [running]    com.spotify.webhelper.plist [Support]

User Login Items: ⓘ

    Safari    Application  (/Applications/Safari.app)

    Android File Transfer Agent    Application  (~/Library/Application Support/Google/Android File Transfer/Android File Transfer Agent.app)

    HP Scheduler    Application  (/Library/Application Support/Hewlett-Packard/Software Update/HP Scheduler.app)

    HPEventHandler    Application  (/Library/Printers/hp/hpio/HPEventHandler.app)

Other Apps: ⓘ

    [running]    [0x0-0x10010].com.google.android.mtpagent

    [running]    [0x0-0x1d01d].com.etresoft.EtreCheck

    [running]    [0x0-0xc00c].com.hp.HPEventHandler

    [running]    com.hp.devicemonitor

Internet Plug-ins: ⓘ

    Flip4Mac WMV Plugin: Version: 2.4.1.4 [Support]

    FlashPlayer-10.6: Version: 20.0.0.286 - SDK 10.6 [Support]

    JavaAppletPlugin: Version: 13.9.8 - SDK 10.6 Check version

    Flash Player: Version: 20.0.0.286 - SDK 10.6 Outdated! Update

    QuickTime Plugin: Version: 7.6.6

    OfficeLiveBrowserPlugin: Version: 12.2.0 [Support]

    Google Earth Web Plug-in: Version: 7.1 [Support]

    Mozillaplug: Version: 1.0

    SharePointBrowserPlugin: Version: 14.1.0 [Support]

    Silverlight: Version: 4.0.60831.0 [Support]

    iPhotoPhotocast: Version: 7.0 - SDK 10.7

Safari Extensions: ⓘ

    AdBlock

Audio Plug-ins: ⓘ

    iSightAudio: Version: 7.6.6

3rd Party Preference Panes: ⓘ

    AppTrap  [Support]

    Flash Player  [Support]

    Flip4Mac WMV  [Support]

    MacFUSE  [Support]

    Tuxera NTFS  [Support]

Time Machine: ⓘ

    Time Machine information requires OS X 10.8 "Moutain Lion" or later.

Top Processes by CPU: ⓘ

         4%    WindowServer

         2%    mdworker

         1%    ps

         1%    WebProcess

         1%    Dock

Top Processes by Memory: ⓘ

    459 MB    WebProcess

    242 MB    Safari

    80 MB    App Store

    41 MB    WindowServer

    35 MB    mds

Virtual Memory Information: ⓘ

    519 MB    Free RAM

    1.49 GB    Used RAM

    0 B    Swap Used

Diagnostics Information: ⓘ

    Feb 10, 2016, 02:55:10 PM    Self test - passed