iMac 27-inch Late 2012 and Late 2013 Repair and Upgrades

The 27-inch Late 2012 and Late 2013 iMac (A1419) is one of the easier Intel iMacs to bring back up to speed. Its memory sits behind a door on the back, the hard drive or Fusion Drive can make way for an SSD from $599, and OpenCore Legacy Patcher takes it past Apple's Catalina limit to Sequoia, from $249. With these machines asking about $220 on Gumtree, an SSD plus the patcher (from $848) is worth it only if you specifically want to keep this iMac, and a replacement screen from $699 almost never is.

Late 2012 or Late 2013: how to check

Both carry A1419 on the underside of the stand, next to the serial number. So does every 27-inch Retina 5K model up to 2017, which means the A-number tells you the size and shape but never the year. Check one of these instead:

• About This Mac in the Apple menu reads "iMac (27-inch, Late 2012)" or "iMac (27-inch, Late 2013)". A 5K model has "Retina 5K" in its name.
• System Information, opened by holding Option in the Apple menu, gives the Model Identifier under Hardware Overview: iMac13,2 for Late 2012, iMac14,2 for Late 2013.
• The serial number from the stand, entered at checkcoverage.apple.com, names the model even when the iMac will not start.

On this pair the year matters more than usual, because the SSD slot inside is a different type on each.

Specifications side by side

Upgrades and what they cost

SSD from $599 (display removal)

Each year has a 3.5-inch SATA bay plus a blade SSD connector on the logic board, and the connector is there even on machines sold with only a hard drive. What differs is the connector type:

• Late 2012: a custom SATA blade. NVMe and PCIe blades, and the adapters sold for them, will not work.
• Late 2013: a PCIe blade, so a standard NVMe SSD fits with an adapter. Booting from it needs High Sierra or later, so we bring the iMac up to its latest official macOS before the swap.

From Late 2012 on, the glass is laminated to the LCD and the display is held on with adhesive strips, so reaching any drive means cutting it free and refitting it with new adhesive. Our iMac SSD upgrade covers that: from $599 with a 500GB SSD or from $699 with 1TB, plus data transfer and macOS setup.

Swap the 3.5-inch hard drive itself and there is a second trap. Apple's factory drives report their temperature through custom firmware; without that signal from a retail drive, the fans spin up to maximum. We fit an in-line thermal sensor for that bay when it applies.

Fusion Drive models pair a 128GB flash module with the hard drive and present them as one volume. Replace either half and macOS sees two drives; Apple's command to rejoin them deletes all data. We copy your files off before touching a Fusion setup, and if the hard drive half is failing but still readable, data recovery starts from $249.

RAM from $329 (easy)

Press the small grey button just above the power socket and the memory door lifts off. There are four slots for 1600MHz DDR3 SO-DIMMs, 32GB maximum, and 8GB came as standard. Through our iMac RAM upgrade we fit 16GB from $329, fit memory you bought from $89, or quote 32GB. Apple publishes instructions for this door, so you can also do it yourself.

Hinge repair: from $299 (involved)

If the screen will not hold its angle, the hinge spring is the known weak point on these two models. Apple ran a repair program for 27-inch iMacs shipped between December 2012 and July 2014, extended to five years from purchase; the cause was plastic washers in the spring mechanism. That program has ended. The repair means removing the display and stripping the internals to reach the hinge, and we do it from $299.

Other repairs

Screen replacement is from $699, the power supply from $479, a thermal service and fan clean from $249, and logic board repair from $449. See iMac screen replacement and logic board and power supply repair for detail.

Catalina officially, Sequoia with the patcher

Apple's final release for both models is Catalina 10.15. Current Firefox and Zoom still run on it; Chrome, which now needs Ventura, does not, and Microsoft 365 has stopped updating. Catalina also sits well outside the three macOS versions Apple still patches for security.

The patcher installs Big Sur through Sequoia 15 on both, and we do it from $249 with patches and post-install checks. From Ventura on, the Nvidia Kepler graphics count as "Legacy Metal", which brings some known limits:

• Live Text and face detection in Photos are off by default.
• From Sonoma, Safari fails to play DRM-protected video on most graphics chips of this kind.
• Photos cannot edit portrait shots.
• On Sequoia, Software Update can stall on a spinning circle, and dynamic wallpapers fail.

The processors differ as well. The Late 2013's Haswell chip has AVX2, while the Late 2012's Ivy Bridge chip lacks it, and some newer apps will not run without it. Every macOS update removes the root patches until they are reapplied, so automatic updates stay off. Read newer macOS on an old iMac for the security side before deciding.

Target Display Mode

Both models are on Apple's list of iMacs that can serve as a display for another Mac, using a Thunderbolt cable and Command-F2. The condition most people miss: Apple requires the iMac itself to run High Sierra 10.13.6 or earlier. On Catalina, or patched to something newer, it falls outside that requirement. The Mac plugged into it must have been introduced in 2019 or before, on Catalina or an earlier version, so this suits an older Mac, not a new one.

Known faults

• Hinge springs. Covered by Apple's hinge program, now ended (see above).
• 3TB hard drives. Apple's replacement program covered Late 2012 27-inch iMacs with a 3TB drive sold between December 2012 and September 2013. It has ended too. If your iMac still has one, back it up and plan on an SSD.
• Fans at full speed after a drive swap. The missing temperature reading described above.
• Fusion Drive split into two. One half replaced, and the pair no longer works as one volume.

Repair or replace: the numbers for a 27-inch 2012–2013

On Gumtree in September 2026, working units were asking $100 to $350, with a median of about $220 and private Sydney listings between $130 and $220. One upgraded to a 1TB SSD and 32GB was listed at $695. Refurbished units from an online reseller started at about $405 for a Late 2013 and $506 for a Late 2012. Against that:

An SSD with the patcher now costs from $848. That is about a third of the $2,399 base 24-inch M4 iMac and leaves you with a quick 27-inch Mac, but it is almost four times the median asking price for the whole machine, and a private 27-inch 5K 2017 sells for about $475. So it is worth doing only if you specifically want to keep this iMac; otherwise, buying a used 5K 2017 or 2019 and upgrading that may be better value. A screen from $699 is more than three times the median asking price, which rules it out for most owners. If the screen or board has failed, a $150 bench diagnostic, waived if you go ahead with the repair, tells you what went wrong, and our guide on repairing or replacing an old iMac helps with the call.

There is no pickup or onsite service for iMacs: you bring the machine to our workshop near Castle Hill, and customers come to us from the Hills District and all over Western Sydney. Quotes over the phone are free, SSD and RAM jobs usually take one to two business days when parts are in stock, and the warranty is 12 months on parts and labour.

Related generations: the older 2009–2011 iMacs with removable glass, the 21.5-inch 2012–2014 on the same slim design, and the 27-inch 5K 2014–2017 that shares the A1419 number. Every model is listed on our iMac repair and upgrades hub.

Get a quote

Questions

Can I put an NVMe SSD in a Late 2012 iMac?

No. The blade connector in the 27-inch Late 2012 is a custom SATA type, and NVMe or PCIe blades and their adapters will not work in it. You can fit a SATA SSD in the 3.5-inch bay or use a SATA-type blade instead. The Late 2013 is different: its PCIe slot takes an NVMe SSD through an adapter once the Mac is on High Sierra or later.

What is the maximum RAM for a 27-inch Late 2013 iMac?

32GB, across four slots of 1600MHz DDR3 SO-DIMM behind the rear memory door. The Late 2012 has the same limit and the same door, which opens with the button above the power socket. We fit 16GB from $329, install memory you supply from $89, or quote a full 32GB.

Can a 27-inch Late 2013 iMac run macOS Sequoia?

Yes, with OpenCore Legacy Patcher, even though Apple's own support ended at Catalina. The Nvidia Kepler graphics are treated as Legacy Metal, so expect Live Text to be off by default, trouble with DRM video in Safari and occasional Software Update stalls on Sequoia. Its Haswell processor has AVX2, which helps with newer apps. We install and check it from $249.

Why will my 27-inch iMac screen not stay up?

On Late 2012 and Late 2013 models the known cause is the plastic washers in the hinge's spring mechanism. Apple's hinge repair program for 27-inch models shipped December 2012 to July 2014 is over. Fixing it is a bigger job than it looks, because the display has to come off and most of the internals have to come out first. We repair it from $299.

Why does my Fusion Drive now show as two drives?

That is what macOS shows after one half of a Fusion Drive, the 128GB flash module or the hard drive, has been replaced. Apple's reset command joins them again but deletes all data, so do not run it until your files are safe. We recover data from readable drives from $249 and can replace the Fusion Drive with a single SSD from $599.

Was there an Apple program for 3TB hard drives in the 2012 iMac?

Yes. Apple ran a 3TB hard drive replacement program covering 27-inch Late 2012 units with 3TB drives sold from December 2012 through September 2013. That program has ended, so any repair now is paid. If your iMac still runs its original 3TB drive, back it up and consider moving to an SSD, from $599 with 500GB.