Western Digital WD400JB 40GB 3.5" IDE Hard Drive WD Caviar Enhanced

Western Digital WD400JB 40GB 3.5" IDE Hard Drive WD Caviar Enhanced

The Western Digital WD400JB is a 40GB 3.5-inch internal hard drive from the WD Caviar series, using a Parallel ATA (IDE/PATA) interface. It is an Enhanced IDE (EIDE) drive designed for desktop computers with standard 40- or 80-conductor IDE ribbon cable connections. Manufactured in May 2003, this drive represents the mid-2000s era of desktop storage before Serial ATA (SATA) became the standard interface.

Specifications & What's Included

• Model: WD400JB / WD400JB-00ENA0
• Capacity: 40 GB (LBA 78,165,360 sectors)
• Interface: IDE / PATA (Enhanced IDE)
• Form Factor: 3.5-inch internal
• Drive Series: WD Caviar
• Power: 5VDC @ 0.80A, 12VDC @ 0.45A
• DCM: ESBACT2CH
• Manufactured: 04 May 2003 — Product of Thailand
• Includes: hard drive only (no cables or brackets)

Applications

The WD Caviar JB series was Western Digital's performance-oriented Parallel ATA (PATA/IDE) desktop line, featuring an 8MB cache buffer at a time when most budget drives shipped with 2MB. These drives were commonly used in desktop PCs running Windows XP and earlier operating systems, and they remain compatible with any system featuring a standard 40-pin IDE header. Today the WD400JB sees use as a replacement drive in older desktop builds, retro computing projects, legacy industrial PCs, and CNC or embedded control systems that rely on IDE storage and cannot accept SATA drives. The standard 3.5-inch form factor fits any full-size desktop drive bay.