IBM 49G2131 - 20-10VDC 2.20-3.38A AC Adapter

IBM 40W 20-10V AC Adapter 4-Pin D Plug for ThinkPad 700 700C 720 720C

Description

Original IBM variable-voltage AC adapter for early ThinkPad systems that use the 4-pin D-shaped DC jack (marked DC-IN 20V with G-E-S-+ legend). The sense pin automatically negotiates the correct output within ~10–20V, and the brick delivers a true 40W—required for ThinkPad 720/720C and recommended for 700C (backward-compatible with 700).

Key Features

☑️ Correct 4-pin D-shaped IBM plug (keyed; G-E-S-+ pinout)
☑️ Variable 20–10V output via sense-pin control
☑️ True 40W capacity for stable operation on 720/720C; safe for 700/700C
☑️ Universal input 100–240V, 50/60Hz (IEC AC power cord)

Technical Specifications

• Input: 100–240V AC, 50/60Hz
• Output: 20–10V DC (sense-controlled), 2.20–3.38A, 40W max
• Connector: IBM 4-pin D DC plug (keyed)
• AC Cord: Standard 3-prong IEC (included when available)

Interchangeable Part Numbers — 40W Family (use these)

• P/N 49G2192
• P/N 49G2194
• FRU 49G2196
• P/N 49G2131
• P/N 35G4796
• P/N 48G8942

(All PNs above are the same 40W, 20–10V variable-output adapter with the IBM 4-pin D plug.)

Not interchangeable/underpowered (same plug, 25W): 44G3737, 44G3808.

What’s Included

☑️ IBM 40W AC Adapter (one of the interchangeable PNs above)
☑️ Detachable AC power cable (when available)

✅ Confirmed Compatibility

Please note that the following list is not exhaustive. Compatibility depends on your system’s specific configuration. It’s essential to verify compatibility with your system manufacturer prior to installation.

✔ IBM ThinkPad: 700, 700C, 720, 720C