Amazon.com: 2GB Kit Apple PowerMac G5, iMac G5 Memory Upgrades (M9298G/A) 2 x 1GB DDR PC3200 DIMMs: Computers & Accessories. Power Mac G5 systems with PCI expansion slots have four RAM slots and systems with PCI-X or PCI-Express (PCIe) expansion slots have eight RAM slots. This information is provided on the specs page for each model, but for your convenience, details regarding compatible memory, number of memory slots, and maximum supported RAM also are provided below. Crucial Memory and SSD upgrades - 100% Compatibility Guaranteed for apple Power Mac G5 (Quad 2.5GHz DDR2) - FREE US Delivery. Rember is actually a GUI for the popular command line memory testing tool called. Note 3: If you get a CAN'T OPEN error, it means that you forgot to plug in your USB stick BEFORE powering on the computer, so turn the Mac off and start over from step #1. To date, Macintosh Repository served 1269024 old Mac files, totaling more than 242456.8GB!
System cleanup in one click
Few things are more frustrating than your Mac telling you it has run out of memory when you're trying to be productive. It's more frustrating when you've ignored the problem for quite some time and your Mac's limitations simply won't let you put a solution on hold any longer.
- How to get rid of low memory notifications
Usually, a popup warning isn't the first sign that something is amiss. You may have noticed that your Mac isn't running as fast as it used to, with the fan louder than normal as if it's struggling to carry a heavy load up a hill.
Although Macs are wonderful computers, they have limitations. Thankfully, there is plenty you can do to resolve this problem and get your Mac operating smoothly again.
Reduce memory usage with Setapp
Instead of manually deleting files, get Setapp. It not only removes the clutter but also gives you full control over memory usage.
Your system has run out of application memory - Fix it
Mac memory usage is often occupied by apps, even browsers like Safari or Google Chrome. In the most dire circumstances, your Mac will toss a warning at you: 'your system has run out of application memory.'
Don't despair – it's solvable. The first thing to note is this is a natural issue; your Mac has a limited amount of RAM. Though more expensive Macs have more RAM, even they can butt against limitations when too many applications are running.
It may also be an app that is hogging all of your resources. This is especially true of older applications which haven't been optimized for modern computer architecture. Websites may also be a culprit.
Check RAM usage on Mac
To check your RAM use on any Mac, take the following steps:
- Open Activity Monitor from your list of applications
Note: You can do this is the Mac's control center, via the Finder in your Mac's dock, or by pressing command-space and typing 'Activity Monitor' in the Spotlight search field. - Toggle to the 'Memory' pane in the Activity Monitor window
As you see in the above screenshot, Activity Monitor shows you all of your processes, sub-processes, and how much memory each is taking up. The most pertinent portion of the window is the bottom, where it shows you the total memory usage, and how it's affecting your Mac.
A better way to monitor your Mac's memory use is with iStat Menus. After installing the app, it makes a home in your Mac's menu bar, and monitors just about everything, including memory, CPU, GPU, disks, and network usage.
You can choose which systems you'd like to monitor in the app itself. Only the items you're monitoring will have an icon in your menu bar. A simple click on the menu bar icon surfaces a drop-down menu of how your Mac is performing at the time, and hovering over each graphic brings up a larger menu, as you can see below.
How to check CPU usage on Mac
Checking CPU use on your Mac is similar to the steps above for checking memory use. For Activity Monitor, you'd make sure to highlight the 'CPU' section of the window. This will show you all the processes using your Mac's CPU at the time.
Similarly, iStat Menus has a 'CPU & GPU' toggle just above the memory section. Activating that will add a CPU and GPU monitor to your Mac menu bar, which has the same interactivity as the memory icon and menu shown above.
How to free up memory on Mac
Knowing how to clear memory on Mac is important, especially if you have a Mac with limited resources. One option is using Activity Monitor:
- Open Activity Monitor on your Mac
- Select an app using a lot of memory
- Click the 'x' icon on the top left of the screen
This is straightforward, but there's a better way. CleanMyMac X has an automated CPU and memory monitors built-in, which can give you a real-time view of memory usage in your Mac's menu bar. It also has a really quick and easy way to free up memory without digging through Activity Monitor and manually shutting down apps.
All you have to do is click the CleanMyMac X icon, select 'Free Up' in the memory pane, and the app takes care of the rest! Oftentimes, it doesn't even shut apps down.
This is a quick fix, but CleanMyMac X takes it a step further in the app itself. Under the app's 'Maintenance' section is an option to 'Free Up RAM,' which helps you clear RAM on Mac. Once you've got this option selected, simply select 'Run' at the bottom of the window, and CleanMyMac X will do a thorough scrubbing of your Mac's RAM, and clear unused files out of the way.
How to get rid of low memory notifications
Most apps are pretty good about how they use your Mac's resources. Having too many open or running in the background can severely limit what your Mac can handle, and is often why a Mac overheats or slows down.
Here are a few tips to reduce high memory usage manually if you're experiencing unique warnings or issues:
Fix 'kernel_task', a high CPU usage bug
You may have noticed through Activity Monitor something called kernel_task absorbing a large amount of processing power. One of the functions of kernel_task is to help manage CPU temperature; you may find that your Mac fan is loud and always on, even if the device isn't hot to the touch.
kernel_task usually performs this way when one or more applications are trying to use too much CPU. Unfortunately, one of the potential downsides is a Mac can overheat to such an extent that internal systems are damaged, sometimes irreparably.
Working through the following steps in this article is one way to avoid similar problems. If none of this work and kernel_task is still absorbing a high percentage of your CPU, then one or more of the following could be the cause:
- Cooling system inefficiency
- A failed or disconnected temperature sensor
- Another hardware issue, including a worn out batter
- Your System Management Controller needs a rest
If you're experiencing severe issues, Apple recommends a system management controller (SMC) reset. It's essentially a hard reset for your Mac, and should help your RAM and other hardware components start from scratch. Keep in mind you won't lose any data in this process.
Reduce memory usage in Finder
One common culprit for RAM issues is Finder, your Mac's file manager. If iStat Menus or Activity Monitor has highlighted Finder as using hundreds of MBs of RAM, there is an easy solution: change the default display for a new Finder window so it doesn't show All My Files.
- Click on the Finder icon in the Dock and click on the Finder menu, then select Preferences
- Click on General. Under 'New Finder windows show', click the dropdown menu and choose any option except All My Files
- Close Preferences, press Alt-Control, and click on the Finder icon in the Dock. Click Relaunch
Finder will now relaunch with new windows opening at the option you selected in step two.
Improve Chrome's Task Manager
Chrome is a popular browser, but it's a resources hog! Chrome uses a GPU Process as standard, which means it speeds up the loading of web pages, which can be great except at times when your computer is struggling with insufficient RAM.
Here's how:
- Open Chrome on your Mac
- On the right side of the Chrome window, select the three-dot menu
- Select 'More tools'
- Select 'Task Manager'
- Select a Chrome process you'd like to kill
- Select 'End Process' at the bottom right of the window
Here's another way to reduce Chrome's use of your Mac's memory:
- Open Chrome on your Mac
- On the right side of the Chrome window, select the three-dot menu
- Select 'settings'
- Scroll to the bottom of the page and select 'advanced'
- Scroll down to 'System,' and toggle 'Use hardware acceleration when available' off
This will affect how Chrome runs on your Mac, and your experience won't be as smooth. You can also remove unused or unwanted Chrome extensions to help it use less resources on your Mac.
Get CMM X to free up space
Install CleanMyMac X and streamline the entire process of memory management on Mac. Clever memory usage control done for you.
Clean up browsers
In every browser you use regularly, there are always going to be extensions and popups that take up space and use RAM. You can manage each one manually, or use a tool such as CleanMyMac X to identify and delete them.
In the CleanMyMac X app is a section titled 'Extensions,' which lists each extension you have for your browser or browsers. All you have to do is view the list of extensions, select the ones you no longer want, and remove them. It's really that simple!
Disable login items
Login items, browser extensions, and preference panes, such as Flash, are another common source of memory usage. Most of us have several installed that we rarely use, but which hog memory and reduce performance.
One way to do this is through System Preferences:
- From your Mac menu bar, select 'System Preferences'
- Select 'Users & Groups'
- Select 'login items'
- Deselect items you no longer want active at login
Another way, one that is even quicker, is to employ CleanMyMac to identify and cleanup login items.
- Open CleanMyMac X
- Under 'Speed,' select 'Optimization'
- Select 'login items'
You can remove all login items, or select the ones you'd like to remove individually on the right side of the window.
Disable desktop widgets
Older Macs running a version of macOS older than Catalina can disable widgets. Desktop widgets can provide a useful shortcut to apps you need to access fairly often. But they can take up processing memory that is slowing your whole Mac down. One way to close them completely is in System Preferences.
Go to: Mission Control > switch off the Dashboard
Declutter your desktop
Apple's built in decluttering tool is handy for many. All you have to do on your cluttered desktop is right-click, then select 'Use Stacks.' This places all of your desktop files into folders unique to their filetype, like 'screenshots' and 'images.'
A better way is to use Spotless, an app that gives you far more control over how your Mac is organized. It has several triggers for automated cleanup of files on your desktop, placing them wherever you see fit. It's particularly useful for power users who produce several files daily, but don't want to take the time to place each in a respective folder.
You can also select many files on your Mac desktop, and tell Spotless to tidy them up. You always have full control!
Schedule regular cleanups
Constant use of your Mac, or leaving it on all the time, will slow it down over time. Shutting it down and restarting is a traditional way of 'cleaning up' a computer.
We also like CleanMyMac X's scheduled cleanup feature. Telling the app when you'd like to perform a thorough cleaning up of your Mac's system is a method many prefer to shutting down and restarting often. It has the upshot of removing files and folders you no longer use, and cleaning up tasks that are slowing your Mac down behind the scenes. A simple shutdown may not do this.
Keeping your Mac in tip-top shape is critical. While we'd all like to think computers are brilliant little devices that can handle anything, they need some care, too.
All of the apps mentioned in this article help with taking care of your Mac, and protecting your investment. Best of all they're each free as part of a seven day trial of Setapp. Give it a try today!
Meantime, prepare for all the awesome things you can do with Setapp.
Read onSign Up
Choose your iMac model
If you're not sure which iMac you have, you can identify your iMac and then select it from the list below.
27-inch
24-inch
21.5-inch
- iMac (Retina 4K, 21.5-inch, 2019)*
- iMac (Retina 4K, 21.5-inch, 2017)*
- iMac (21.5-inch, 2017)*
- iMac (21.5 inch, Mid 2014)*
- iMac (21.5-inch, Late 2013)*
- iMac (21.5-inch, Late 2012)*
20-inch
17-inch
* Memory is not removable by users on iMac (21.5-inch, Late 2012), iMac (21.5-inch, Late 2013), iMac (21.5-inch, Mid 2014), iMac (21.5-inch, 2017), iMac (Retina 4K, 21.5-inch, 2017), and iMac (Retina 4K, 21.5-inch, 2019). If the memory in one of these computers needs repair service, contact an Apple Retail Store or Apple Authorized Service Provider. If you’d like to upgrade the memory in one of these models, an Apple Authorized Service Provider can help. Before you schedule an appointment, confirm that the specific Apple Authorized Service Provider offers memory upgrade services.
Memory in iMac (21.5-inch, Late 2015), and iMac (Retina 4K, 21.5-inch, Late 2015) is not upgradeable.
iMac (Retina 5K, 27-inch, 2020)
Get memory specifications for iMac (Retina 5K, 27-inch, 2020), then learn how to install memory in this model.
Memory specifications
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB (2 x 4GB DIMMs) |
Maximum memory | 128GB (4 x 32GB DIMMs) |
For optimal memory performance, DIMMs should be the same capacity, speed, and vendor. Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
- PC4-21333
- Unbuffered
- Nonparity
- 260-pin
- 2666MHz DDR4 SDRAM
If you have mixed capacity DIMMs, see the install memory section for installation recommendations.
iMac (Retina 5K, 27-inch, 2019)
Get memory specifications for iMac (Retina 5K, 27-inch, 2019), then learn how to install memory in this model.
Memory specifications
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB (2 x 4GB DIMMs) |
Maximum memory | 64GB (4 x 16GB DIMMs) |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
- PC4-21333
- Unbuffered
- Nonparity
- 260-pin
- 2666MHz DDR4 SDRAM
iMac (Retina 5K, 27-inch, 2017)
Get memory specifications for iMac (Retina 5K, 27-inch, 2017), then learn how to install memory in this model.
Memory specifications
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB (2 x 4GB DIMMs) |
Maximum memory | 64GB (4 x 16GB DIMMs) |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
- PC4-2400 (19200)
- Unbuffered
- Nonparity
- 260-pin
- 2400MHz DDR4 SDRAM
iMac (Retina 5K, 27-inch, Late 2015)
Get memory specifications for iMac (Retina 5K, 27-inch, Late 2015), then learn how to install memory in this model.
Memory specifications
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB |
Maximum memory | 32GB |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
- PC3-14900
- Unbuffered
- Nonparity
- 204-pin
- 1867MHz DDR3 SDRAM
For these 27-inch models
Get memory specifications for the following iMac models, then learn how to install memory in them:
- iMac (Retina 5K, 27-inch, Mid 2015)
- iMac (Retina 5K, 27-inch, Late 2014)
- iMac (27-inch, Late 2013)
- iMac (27-inch, Late 2012)
Memory specifications
These iMac models feature Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB |
Maximum memory | 32GB |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
- PC3-12800
- Unbuffered
- Nonparity
- 204-pin
- 1600MHz DDR3 SDRAM
Installing memory
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After you shut down your iMac and give it time to cool, follow these steps:
- Disconnect the power cord and all other cables from your computer.
- Place a soft, clean towel or cloth on the desk or other flat surface to prevent scratching the display.
- Hold the sides of the computer and slowly lay the computer face-down on the towel or cloth.
- Open the memory compartment door by pressing the small grey button located just above the AC power port:
- The memory compartment door will open as the button is pushed in. Remove the compartment door and set it aside:
- A diagram on the underside of the compartment door shows the memory cage levers and the orientation of the DIMM. Locate the two levers on the right and left sides of the memory cage. Push the two levers outward to release the memory cage:
- After the memory cage is released, pull the memory cage levers toward you, allowing access to each DIMM slot.
- Remove a DIMM by pulling the module straight up and out. Note the location of the notch on the bottom of the DIMM. When reinstalling DIMMs, the notch must be oriented correctly or the DIMM won't fully insert:
- Replace or install a DIMM by setting it down into the slot and pressing firmly until you feel the DIMM click into the slot. When you insert a DIMM, make sure to align the notch on the DIMM to the DIMM slot. Find your model below for specific installation instructions and notch locations:
- iMac (Retina 5K, 27-inch, 2020) DIMMs have a notch on the bottom, slightly left of the middle. If your DIMMs are mixed in capacity, minimize the capacity difference between Channel A (slots 1 and 2) and Channel B (slots 3 and 4) when possible.
- iMac (Retina 5K, 27-inch, 2019) DIMMs have a notch on the bottom, slightly left of the middle:
- iMac (27-inch, Late 2012) and iMac (Retina 5K, 27-inch, 2017) DIMMs have a notch on the bottom left:
- iMac (27-inch, Late 2013) and iMac (Retina 5K, 27-inch, Late 2014, Mid 2015, and Late 2015) DIMMs have a notch on the bottom right:
- iMac (Retina 5K, 27-inch, 2020) DIMMs have a notch on the bottom, slightly left of the middle. If your DIMMs are mixed in capacity, minimize the capacity difference between Channel A (slots 1 and 2) and Channel B (slots 3 and 4) when possible.
- After you install all of your DIMMs, push both memory cage levers back into the housing until they lock into place:
- Replace the memory compartment door. You don't need to press the compartment door release button when replacing the compartment door.
- Place the computer in its upright position. Reconnect the power cord and all other cables to the computer, then start up the computer.
Your iMac performs a memory initialization procedure when you first turn it on after upgrading memory or rearranging DIMMs. This process can take 30 seconds or more, and the display of your iMac remains dark until it's finished. Make sure to let the memory initialization complete.
For these 27-inch and 21.5-inch models
Get memory specifications for the following iMac models, then learn how to install memory in them:
- iMac (27-inch, Mid 2011)
- iMac (21.5-inch, Mid 2011)
- iMac (27-inch, Mid 2010)
- iMac (21.5-inch, Mid 2010)
- iMac (27-inch, Late 2009)
- iMac (21.5-inch, Late 2009)
Memory specifications
Number of memory slots | 4 |
Base memory | 4GB (but is configured to order) |
Maximum memory | 16GB For iMac (Late 2009), you can use 2GB or 4GB RAM SO-DIMMs of 1066MHz DDR3 SDRAM in each slot. For iMac (Mid 2010) and iMac (Mid 2011), use 2GB or 4GB RAM SO-DIMMs of 1333MHz DDR3 SDRAM in each slot. |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
iMac (Mid 2011) | iMac (Mid 2010) | iMac (Late 2009) |
PC3-10600 | PC3-10600 | PC3-8500 |
Unbuffered | Unbuffered | Unbuffered |
Nonparity | Nonparity | Nonparity |
204-pin | 204-pin | 204-pin |
1333MHz DDR3 SDRAM | 1333MHz DDR3 SDRAM | 1066MHz DDR3 SDRAM |
i5 and i7 Quad Core iMac computers come with both top memory slots populated. These computers will not start up if only a single DIMM is installed in any bottom slot; these computers should operate normally with a single DIMM installed in any top slot.
Core Duo iMac computers should operate normally with a single DIMM installed in any slot, top or bottom. ('Top' and 'bottom' slots refer to the orientation of the slots in the pictures below. 'Top' refers to the slots closest to the display; 'bottom' refers to the slots closest to the stand.)
Installing memory
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After you shut down your iMac and give it time to cool, follow these steps:
- Disconnect the power cord and all other cables from your computer.
- Place a soft, clean towel or cloth on the desk or other flat surface to prevent scratching the display.
- Hold the sides of the computer and slowly lay the computer face-down on the towel or cloth.
- Using a Philips screwdriver, remove the RAM access door in the bottom of your computer:
- Remove the access door and set it aside.
- Untuck the tab in the memory compartment. If you're replacing a memory module, gently pull the tab to eject any installed memory module:
- Insert your new or replacement SO-DIMM into the empty slot, noting the orientation of the keyway of the SO-DIMM as shown below.
- After you insert it, press the DIMM up into the slot. There should be a slight click when you seat the memory correctly:
- Tuck the tabs above the memory DIMMs, and reinstall the memory access door:
- Place the computer in its upright position. Reconnect the power cord and all other cables to the computer, then start up the computer.
For these 24-inch and 20-inch models
Get memory specifications for the following iMac models, then learn how to install memory in them:
- iMac (24-inch, Early 2009)
- iMac (20-inch, Early 2009)
- iMac (24-inch, Early 2008)
- iMac (20-inch, Early 2008)
- iMac (24-inch Mid 2007)
- iMac (20-inch, Mid 2007)
Memory specifications
These iMac computers have two side-by-side Synchronous Dynamic Random-Access Memory (SDRAM) slots in the bottom of the computer.
The maximum amount of random-access memory (RAM) you can install in each computer is:
Computer | Memory Type | Maximum Memory |
iMac (Mid 2007) | DDR2 | 4GB (2x2GB) |
iMac (Early 2008) | DDR2 | 4GB (2x2GB) |
iMac (Early 2009) | DDR3 | 8GB (2x4GB) |
Mac G5 Specs
You can use a 1GB or 2GB RAM module in each slot for iMac (Mid 2007) and iMac (Early 2008). Use 1GB, 2GB, or 4GB modules in each slot for the iMac (Early 2009).
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
iMac (Mid 2007) | iMac (Early 2008) | iMac (Early 2009) |
PC2-5300 | PC2-6400 | PC3-8500 |
Unbuffered | Unbuffered | Unbuffered |
Nonparity | Nonparity | Nonparity |
200-pin | 200-pin | 204-pin |
667MHz DDR2 SDRAM | 800MHz DDR2 SDRAM | 1066MHz DDR3 SDRAM |
DIMMs with any of the following features aren't supported:
- Registers or buffers
- PLLs
- Error-correcting code (ECC)
- Parity
- Extended data out (EDO) RAM
Installing memory
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After your iMac cools down, follow these steps:
- Disconnect the power cord and all other cables from your computer.
- Place a soft, clean towel or cloth on the desk or other flat surface to prevent scratching the display.
- Hold the sides of the computer and slowly lay the computer face-down on the towel or cloth.
- Using a Philips screwdriver, remove the RAM access door in the bottom of the computer:
- Remove the access door and set it aside.
- Untuck the tab in the memory compartment. If you're replacing a memory module, untuck the tab and pull it to eject any installed memory module:
- Insert your new or replacement RAM SO-DIMM into the empty slot, noting the orientation of the keyway of the SO-DIMM as shown above.
- After you insert it, press the DIMM up into the slot. There should be a slight click when you seat the memory correctly.
- Tuck the tabs above the memory DIMMs, and reinstall the memory access door:
- Place the computer in its upright position. Reconnect the power cord and all other cables to the computer, then start up the computer.
For these 20-inch and 17-inch models
Get memory specifications for the following iMac models, then learn how to install memory in them:
- iMac (20-inch Late 2006)
- iMac (17-inch, Late 2006 CD)
- iMac (17-inch, Late 2006)
- iMac (17-inch, Mid 2006)
- iMac (20-inch, Early 2006)
- iMac (17-inch, Early 2006)
Memory specifications
Number of memory slots | 2 | ||
Base memory | 1GB | Two 512MB DIMMs; one in each of the memory slots | iMac (Late 2006) |
512MB | One DDR2 SDRAM installed into the top slot | iMac (17-inch Late 2006 CD) | |
512MB | Two 256MB DIMMs; one in each of the memory slots | iMac (Mid 2006) | |
512MB | One DDR2 SDRAM installed into the top slot | iMac (Early 2006) | |
Maximum memory | 4GB | 2 GB SO-DIMM in each of the two slots* | iMac (Late 2006) |
2GB | 1GB SO-DIMM in each of the two slots | iMac (17-inch Late 2006 CD) iMac (Early 2006) | |
Memory card specifications | Compatible: - Small Outline Dual Inline Memory Module (DDR SO-DIMM) format - PC2-5300 - Nonparity - 200-pin - 667 MHz - DDR3 SDRAM | Not compatible: - Registers or buffers - PLLs - ECC - Parity - EDO RAM |
For best performance, fill both memory slots, installing an equal memory module in each slot.
*iMac (Late 2006) uses a maximum of 3 GB of RAM.
Installing memory in the bottom slot
Ram For Mac G5
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After you shut down your iMac and give it time to cool, follow these steps:
- Disconnect the power cord and all other cables from your computer.
- Place a soft, clean towel or cloth on the desk or other flat surface to prevent scratching the display.
- Hold the sides of the computer and slowly lay the computer face-down on the towel or cloth.
- Using a Phillips screwdriver, remove the RAM access door on the bottom of the iMac and set it aside:
- Move the DIMM ejector clips to their fully open position:
- Insert your RAM SO-DIMM into the bottom slot, keeping in mind the orientation of the keyed SO-DIMM:
- After you insert it, press the DIMM up into the slot with your thumbs. Don't use the DIMM ejector clips to push in the DIMM, as this might damage the SDRAM DIMM. There should be a slight click when you seat the memory fully.
- Close the ejector clips:
- Reinstall the memory access door:
- Place the computer in its upright position. Reconnect the power cord and all other cables to the computer, then start up the computer.
Replacing memory in the top slot
After you shut down your iMac and give it time to cool, follow these steps:
- Disconnect the power cord and all other cables from your computer.
- Place a soft, clean towel or cloth on the desk or other flat surface to prevent scratching the display.
- Hold the sides of the computer and slowly lay the computer face-down on the towel or cloth.
- Using a Phillips screwdriver, remove the RAM access door on the bottom of the iMac and set it aside:
- Pull the two levers on each side of the memory compartment to eject the memory module that's already installed:
- Remove the memory module from your iMac as shown below:
- Insert your RAM SO-DIMM into the top slot, noting the orientation of the keyed SO-DIMM:
- After you insert it, press the DIMM up into the slot with your thumbs. Don't use the DIMM ejector clips to push in the DIMM, as this might damage the SDRAM DIMM. There should be a slight click when you seat the memory fully.
- Close the ejector clips:
- Reinstall the memory access door:
- Place the computer in its upright position. Reconnect the power cord and all other cables to the computer, then start up the computer.
If your iMac makes a tone after you install memory
iMac models introduced before 2017 might make a warning sound when you start up after installing or replacing memory:
- One tone, repeating every five seconds signals that no RAM is installed.
- Three successive tones, then a five-second pause (repeating) signals that RAM doesn't pass a data integrity check.
If you hear these tones, confirm that the memory you installed is compatible with your iMac and that it's installed correctly by reseating the memory. If your Mac continues to make the tone, contact Apple Support.
Confirm that your iMac recognizes its new memory
Memory For Power Mac G5
After you install memory, you should confirm that your iMac recognizes the new RAM by choosing Apple () menu > About This Mac.
The window that appears lists the total memory, including the amount of memory that originally came with the computer plus the newly added memory. If all the memory in the iMac has been replaced, it lists the new total of all installed RAM.
Ram For Mac G5
For detailed information about the memory installed in your iMac, click System Report. Then choose Memory under the Hardware section in the left side of System Information.
G5 Power Mac Specs
If your computer doesn't recognize the memory or doesn't start up correctly, confirm that the RAM you installed is compatible with your iMac and that it's installed correctly by reseating the memory. If you continue to have issues with the memory in your iMac, contact Apple Support.