WhatCable Pro is a deep USB-C diagnostics tool designed specifically for Apple Silicon Macs running macOS 14+. While the free version identifies basic cable capabilities, the Pro tier offers advanced, real-time troubleshooting directly from IOKit data—requiring no extra software or root access.

Key Features

• Negotiation Diagnostics: Easily spot bottlenecks by comparing what your Mac port, cable, and connected device support side-by-side.
• Live Power Metering: Displays real-time wattage, voltage, and amperage per port, updating every 2 seconds.
• Hardware & Port Health: Tracks lifetime port errors, resets, and monitors liquid detection (LDCM) sensors.
• Advanced Insights: Offers Power Delivery (PD) contract inspection, cable resistance estimation, and DisplayPort Alt Mode lane mapping.
• Developer Friendly: Includes a CLI monitor mode (whatcable –monitor) and desktop widgets for quick tracking.

What's New:

Version 0.19.2

What's fixed:

• 5K and 6K displays no longer show as 4K in Display Diagnostics. WhatCable already reads your display's true mode straight from macOS, but that reading was only reaching the command-line output, not the Display Diagnostics screen in the app. The screen now uses the same live reading, so an Apple Studio Display reads 5120 × 2880 instead of falling back to the 4K value its spec sheet reports.

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