How to Convert an old iMac into a 5K Monitor

If you’ve got an old iMac lying around collecting dust, did you know you that with a few components and a little DIY, you can turn it into a 5K display?

Although Apple has made it much harder to use an iMac as an external display, with a bit of DIY you can turn it into a standalone 5K monitor that you can use with any Mac.

This is a lot cheaper than buying an Apple Studio Display (starting at $1,599) or any of the excellent alternatives to it.

Apple won’t give old iMacs any trade-in value and you’d be lucky to get a few hundred dollars for it on eBay – so turning an unused iMac into a monitor is great way to give it a new lease of life.

Plus you’ll be doing your bit for the environment instead of dumping it in a landfill.

In this guide, we look at exactly what you’ll need and how to do it.

Why Not Just Use Target Display Mode?

First, it’s useful to understand why you’d even want to go to all the hassle of doing this modification rather than use Target Display Mode or another method.

• Older iMacs (2009–2014) supported Target Display Mode via Thunderbolt or Mini‑DisplayPort, but newer iMacs do not. Target Display Mode allows you to connect an iMac to any Mac and use it as an external 5K display. Although there are other ways to use an iMac as an external display with newer Macs, they’re not as effective as using Target Display Mode – which is why some people resort to physically converting an iMac into a 5K monitor.
• In this tutorial, we show you how to turn the iMac into a pure monitor (i.e., remove or bypass its logic board, and just use the display). The main component you need is a hardware “LCD controller board” (sometimes also called a “driver board”).
• This is a real hardware mod – you’ll need to open the iMac, remove internal components, install a board, connect the panel and backlight, add external inputs, and reassemble.
• You’ll need to make sure you get the right controller board for your specific iMac display panel. Don’t worry, I’ll guide you through this.

What You’ll Need (Tools & Equipment)

Firstly, this isn’t a job for the faint hearted – you’ll need to be comfortable opening-up electronic devices and tinkering with internal components.

The worst part is actually disassembling and re-assembling the Mac – inserting the new components is the relatively easy bit.

Before we begin, I’d recommend having the following tools and equipment:

Core Components

• The right controller board / kit (see steps 1 and 2 below) matched to your panel – this is essential.
• Appropriate power supply (check the board spec: e.g., 12 V or 24 V, current rating).
• Input cable: DisplayPort cable (for full 5K @ 60Hz) or USB‑C cable (if your board supports it).
• Backlight cable / panel connector cable (often included in kit, but check).
• Possibly an adapter or custom cable for panel connection if the board uses a different pin‑layout.

iMac Disassembly Tools

• Set of precision screwdrivers (Torx, Phillips, etc) – many iMacs use Torx screws.
• Opening tools/pry tools: plastic spudgers, suction cups to remove the glass or screen safely.
• Adhesive strips or tape: iMac glass / display often uses strong adhesive. If you remove glass, you may need replacement adhesive strips.
• Anti‑static wrist strap (optional but advisable when working with internal electronics).
• Micro‑fibre cloths and isopropyl alcohol (to clean inside glass/panel before reassembly to avoid dust).
• Work surface with good lighting.

Wiring / Mounting & Finishing

• Double‑sided foam tape, small Velcro or mounting brackets to secure the controller board inside the case.
• Cable ties / zip‑ties to tidy wiring.
• Electrical tape or heat‑shrink tubing (for any custom wire connections).
• Thermal pads or small cooling device if the board runs warm (especially if you leave fan inside).
• Replacement adhesive for re‑attaching glass or bezel if removed.
• A small container or magnetic tray to keep screws safe (iMacs have an insane number of small screws!).

Testing Setup

• Your source computer (Mac) with the output port you plan to use (USB‑C/Thunderbolt or Mini‑DisplayPort/DP).
• External keyboard/mouse if required for initial testing.
• Clear access to the board’s OSD buttons (menu/up/down/power) – you may need to mount a small control board or make holes in the case for the buttons.

Safety & Preparation

Finally, it’s very important you take the following precautions before proceeding:

• Make sure you’ve transferred any files from your iMac to an external SSD or Thunderbolt external drive.
• Power off and unplug the iMac before opening it. You can hold down the power button for 10 seconds to fully discharge the supply capacitors – I still recommend turning it off a good few hours before you open it up to be on the safe side.
• Ground yourself to avoid electrostatic discharge.
• Work slowly and carefully; the LCD panel and glass are very fragile.
• Take photos during disassembly so you remember where cables/screws go!

1. Identify Your iMac Display Panel

Before buying a controller board, you must check exactly which LCD panel your iMac uses. Most 5K iMacs use LG panels with eDP interfaces, but the exact model matters (for example, LM270QQ1 vs LM270QQ2). Some boards, like this one from Amazon, are suitable for both models.

To identify which LCD panel your iMac uses:

1. Open the iMac and carefully inspect the back of the LCD panel for a part number or sticker. To help with the disassembly process, I recommend using the iFix it disassembly guide.
2. Match that to the specifications on controller board listings.
3. Note the connector type, eDP lanes, and power requirements.

Note that if you have to order the Display Panel from a retailer outside your own country, you may face import taxes on them – as you would for the controller board kit (see below).

2. Choose the Right Controller Board Kit

The controller board kit is what allows you to connect devices and your Mac to the iMac. Here are key things to look for when you buy the controller board kit:

• Inputs: Make sure it supports inputs you need (e.g., dual DisplayPort for real 5K, or USB‑C / Type‑C).
• Power: Check the required power adapter (voltage and current).
• Backlight cable: The kit should include or support the backlight cable for your panel.
• OSD (On‑Screen Display): For brightness, contrast, menu – helpful to have control buttons or remote.
• Resolution / Refresh Rate: Confirm it supports 5120 × 2880 @ 60 Hz (or whatever your panel supports).

Example Controller Kits / Board:

Here are some boards / kits that are similar to what you might find via Amazon (or other suppliers):

• LCD Controller Kit for 27″ 5K iMac (LM270QQ2 panel) – supports DP Type‑C, needs 12 V. Amazon, Fruugo, AliExpress and eBay.
• 2HDMI + 2DP 5K HDR LCD Controller Board Kit for iMac A1419 LM270QQ1 (supports FreeSync, 5K @ 60 Hz). Amazon, Fruugo and eBay.
• DIY 5K controller board kit (DP 1.4 Type‑C) for iMac A1419/A2115 27″. Amazon and AliExpress

If you’re having trouble finding controller kits or boards, try more general search terms like “5K LCD controller”, “iMac A1419 / A2115”, “LM270QQ1 or QQ2” .

My advice is also to double-check seller ratings, and ask for a photo of the board and part‑numbers to be sure you’re getting the right thing.

I’d also recommend looking for safety certificates or safety assurances although I found these few and far between.

3. Disassemble the iMac

Warning: This is the riskiest part. The display glass and panel are fragile, and iMacs are glued together. If the panel slips or breaks, it’s so expensive to replace that you might as well just buy a new 5K display!

1. Power off and unplug the iMac.
2. Remove the glass and LCD: use the correct tools, work slowly, and carefully lift the panel.
3. Take out the iMac logic board and other components to make room. (You don’t need to re-use the original logic board for this project, unless you’re keeping it for other reasons.)

Important: Keep track of where all the cables and screws came from as you disassemble the iMac! This is where taking photos helps.

4. Install the Controller Board

1. Position the controller board securely inside the iMac chassis (consider mounting location, heat, and stability).
2. Connect the LCD cable from the panel to the controller board.
3. Connect the backlight cable.
4. Plug in the power supply to the controller board but don’t power up yet.
5. Connect your input source (e.g., connect a DisplayPort or USB-C cable from your Mac / PC to the board).

Be very careful not to short anything: don’t let metal touch the board’s contacts improperly.

5. Power On & Test

1. Power on the controller board (via its DC input).
2. Use the OSD to adjust brightness / menu settings.
3. On your source computer, set the output resolution / refresh rate to 5K (5120×2880) if supported.
4. Check that the display works: you should see signal, and the backlight should light up.

If it doesn’t work:

• Check all cable connections.
• Make sure the power supply meets the board’s specification.
• Look at OSD settings (sometimes input mode needs to be switched).
• Check the board documentation / manual.

6. Adding A Webcam (Optional)

Before you re-seal everything, you should consider whether you want your iMac to have a webcam and speaker.

Once your iMac is functioning as a standalone 5K display, you’ll need a separate webcam solution because the built-in FaceTime camera no longer works – it’s tied to the original logic board, which is no longer in use.

Option 1: Use an External USB Webcam (Recommended)

This is the simplest and best-quality option.

Why choose it:

• Plug-and-play with any Mac.
• Modern webcams offer drastically better image quality than old iMac FaceTime cameras.
• No internal modding required.

Popular choices:

• Logitech Brio 4K
• Insta360 Link (AI tracking)
• Anker PowerConf C200
• Any 1080p USB-C webcam if you want a budget option.

How to mount it:

• Clip it to the top of the iMac bezel (even the thick older bezels hold clips securely).
• Or use a small tripod/desk stand behind the iMac if you prefer not to clip it.

Option 2: Install the Original iMac Webcam Internally (Advanced)

You can access the original iSight/FaceTime HD camera, but:

• It no longer communicates via the iMac motherboard.
• You would need to extract its tiny camera module, rewire it, and convert it using a USB UVC interface board – which is not widely available and requires soldering.
• The image quality is outdated (720p on most pre-2017 models).

So basically, you can reuse it, but it’s almost always easier and better to attach a modern external webcam.

Option 3: Use a DSLR or Mirrorless Camera (Most Expensive)

If you need streaming-quality video:

• Connect your camera using an HDMI-to-USB capture card (Elgato Cam Link 4K or cheap UVC alternatives).
• Mount the camera above or behind the iMac.
• This gives beautiful depth-of-field and great low-light performance.

7. Adding Microphone & Speaker (Optional)

Since the iMac’s built-in speakers and mic also won’t work after conversion, you’ll need to use a few workarounds:

Microphone Options

• USB microphones like the Blue Yeti or Elgato Wave.
• Headset mic (USB-C or Bluetooth).
• Desktop boundary mic if you prefer minimal desk clutter.

Speaker Options

• USB-powered speakers
• Bluetooth speakers
• Soundbar placed under the iMac
• Or use the audio output of an eGPU/dock if your setup includes one.

8. Reassemble the iMac

Once you’re confident that the screen works correctly and you’ve decided whether to restore microphone, speakers and webcam, it’s tine to put it all back together.

1. Carefully re-seat the LCD panel in the iMac housing.
2. Re-apply adhesive or use the correct adhesive strips (if needed) to fix the glass.
3. Mount the controller board securely.
4. Refit any internal components you removed (or decide whether to leave them out – depends if you want the iMac to be just a monitor).
5. Close everything up, but keep access to the board control buttons / power supply if you think you might need to tweak things later.

9. Configure & Use

• On your source device (Mac / PC), configure display settings for best performance.
• If needed, use the controller board’s OSD to tweak brightness, contrast, color, and so on.
• Bear in mind: because the iMac’s original logic board is removed, you’ll lose its built-in features (webcam, speakers, USB ports, etc.) unless you’ve repurposed them separately.

Safety, Risks & Trade‑offs

There are a number of issues to be aware of if you go ahead with this modification.

• Warranty & Reversibility: This mod is effectively permanent (or at least hard to reverse). Opening an iMac often breaks adhesive seal, and there’s risk of damaging the panel.
• Safety: I noticed that many of the controller board kits don’t have any safety certifications so be careful about purchasing those that may be dubious.
• Cost: Depending on the board and shipping, it may cost $150 – $350+ (£100–£300+) (plus power supply, tools).
• Heat & Power: The controller board and panel will draw power and may generate heat – consider ventilation.
• Experience Required: You should be comfortable working with delicate electronics. This is not a beginner-level mod.
• Trade-off: Instead of doing this, you could buy a second‑hand 5K monitor or a newer display but part of the appeal is re‑using / recycling.

Alternative (Non-Hardware) Solutions

If you’re not comfortable or confident to attempt any of this, there are software / third party based alternatives that allow you to use an iMac as an external monitor.

Suggestions include:

• Luna Display (Mac-to-Mac mode): lets you use another Mac (or iMac) as an external display.
• Duet Display, screen sharing, or other remote desktop tools can work – but may not give true 5K resolution or low latency.

However, as mentioned earlier, they are inferior to converting your iMac into a display in terms of quality and performance.

Need More Help?

If you get stuck at any stage, I recommend checking-out this developer’s experiences converting his iMac into a 5K display.

Luke Miani also has an excellent video walk-through of how he did it.

Summary: It’s Doable If You Have The Time, Equipment & Patience

As you can see, converting an old iMac into a 5K display is not impossible, especially for 27″ Retina iMacs with the right panel.

But it’s definitely not a plug-and-play solution; it involves taking apart the iMac, fitting a controller board, and handling delicate electronics.

My advice is make sure you do lots of research: identify the exact panel model, choose a reliable controller board, and make sure you have all the tools and parts.

And don’t rush it – make sure you’ve got plenty of time to tackle this. Especially when it comes to sticking everything back together, give yourself plenty of time as rushing it will only ruin all your hard work.

If you’re confident enough to give it a go, it’s a very rewarding way to “upcycle” an old Mac and and give your iMac a second lease of life.