Apple is testing a high-end iMac configuration with its upcoming M5 Max chip, according to leaked kernel debug kit files obtained by MacRumors. The internal software references an iMac with identifier J833c running platform H17C, which corresponds to the M5 Max chip codenamed "Sotra C."
The leak originated from Chinese social media platforms Weibo and BiliBili before circulating to Western tech publications. Apple engineers use these kernel debug kits to enumerate unreleased hardware through internal identifiers, platform names, and chip codename mappings.
This potential iMac Pro would mark Apple's first truly high-end all-in-one desktop since the company discontinued the 27-inch Intel iMac in 2022. The original iMac Pro launched in late 2017 with a $4,999 starting price but was discontinued without a direct Apple Silicon replacement.
Bloomberg's Mark Gurman has previously reported Apple was "working on a larger-screened iMac aimed at the professional market" following the Apple silicon transition. Analyst Ming-Chi Kuo has also pointed to a pro-focused iMac returning to Apple's lineup.
The M5 Pro, M5 Max, and M5 Ultra chips are scheduled to launch in the first half of 2026. An updated Mac Studio could offer the M5 Ultra configuration, making it Apple's most powerful desktop hardware rather than the iMac Pro.
The leaked debug kit reveals numerous other Mac configurations in testing. These include 14-inch and 16-inch MacBook Pro variants with M5 Pro and M5 Max chips, plus a 14-inch MacBook Pro with the M6 chip.
Additional configurations show 13-inch and 15-inch MacBook Air models with M5 chips, Mac mini models with M5 and M5 Pro, and new Mac Studio variants with M5 Max and M5 Ultra. The leak also lists a MacBook with an A18 Pro chip, believed to be a new budget model.
The files reference devices used exclusively for internal testing, such as iPad minis running tvOS and MacBooks with A15 chips. This suggests the M5 Max iMac entry could reflect a test platform rather than a product destined for retail stores.
Apple's current M4 iMac serves consumer markets with colorful designs and everyday performance. Professional users have relied on Mac mini or Mac Studio configurations paired with external displays like the Studio Display or Pro Display XDR.
The M5 Max chip would represent Apple's second-fastest processor tier, positioned between the M5 Pro and rumored M5 Ultra. Current M4 Max chips feature 14 or 16 CPU cores, 32 or 40 GPU cores, and support for 36GB to 128GB of unified memory.
If launched, an M5 Max iMac would compete directly with Apple's own 14-inch and 16-inch MacBook Pro laptops featuring the same chip. The all-in-one design offers cleaner cable management but lacks the portability of laptop configurations.
Apple has maintained radio silence about professional iMac development for months. The company could be rigorously testing products that never reach production, making this leak suggestive rather than definitive.
The kernel debug kit leak follows a separate iOS 26 code leak that revealed over 30 Apple devices potentially launching in coming years. Both incidents highlight Apple's ongoing internal testing across multiple product categories.
Professional users seeking 27-inch iMac replacements currently face compromises between Mac Studio setups and aging standalone displays. The Studio Display uses a standard LCD panel with 60Hz refresh rate and does not support mini-LED, OLED, or ProMotion technology. The Pro Display XDR features mini-LED backlighting with 576 local dimming zones but is limited to 60Hz refresh rate and does not support OLED or ProMotion.
An Apple Silicon iMac Pro would address this gap with integrated high-performance computing and contemporary display technology. The all-in-one format eliminates cable clutter while maintaining Apple's design aesthetic.
The leaked information provides the strongest evidence yet that Apple continues developing professional iMac hardware. Previous rumors have circulated since 2022 without concrete product launches.
Apple typically announces new Mac hardware during its Worldwide Developers Conference in June or special fall events. The M5 chip family's expected 2026 timeline suggests any iMac Pro announcement would occur next year.
All leaked information should be treated with appropriate skepticism until Apple makes official announcements. Internal testing doesn't guarantee commercial product releases, though the consistency across multiple sources strengthens the rumor's credibility.
