Genuine ASUS A20-240P1A ADP-240EB BC 240W AC Adapter Charger

When a 240W ASUS gaming laptop starts draining its battery while plugged in, capping GPU clocks, or flashing a charger-wattage warning, the adapter is usually the culprit. The A20-240P1A (ASUS's internal model) — also stamped ADP-240EB BC as the manufacturing part number — is the high-output brick these machines were designed around. This guide covers what it delivers, why you can't safely substitute a smaller one, and the checks worth doing before you buy.

Two part numbers, one adapter

People often worry they've found the "wrong" charger because the listing shows two codes. They refer to the same product. A20-240P1A is ASUS's model designation, while ADP-240EB BC is the OEM part number from the contract manufacturer that builds it. If your original adapter's label shows either code at 20V / 12A / 240W, you're looking at the correct replacement family.

The spec at a glance

Why 20V and 240W aren't negotiable

The voltage is the safety-critical figure. A 240W ROG or TUF laptop expects exactly 20V; a higher voltage can stress or damage the charging circuit, while a lower one typically means no charge at all. Note that this is different from older 19.5V ASUS bricks — 20V and 19.5V units are not freely interchangeable, so check the decimal on your label.

The 240W rating exists because these laptops can pull close to that under a combined CPU + GPU load. Plug in a 180W or 200W adapter and the system protects itself by throttling performance and topping up the battery more slowly — and during heavy gaming the battery may discharge even while connected. Current is a ceiling, not a target: a same-voltage adapter rated for equal or higher wattage is the safe choice; going below the original 12A is what causes the slowdowns.

What the five protections actually do

Genuine ASUS bricks build in multiple protection circuits. These aren't marketing letters — each guards against a specific failure mode, which is exactly what cheap unbranded adapters tend to skip:

Genuine vs. generic: how to tell

• Weight and build: a real 240W brick is dense and substantial; suspiciously light units often skimp on internal components.
• Label detail: genuine labels print both A20-240P1A and ADP-240EB BC, the full 20V/12A/240W rating, regulatory marks, and clean, sharp text.
• Heat under load: a properly rated adapter runs warm, not hot; an under-spec'd clone overheats during gaming.
• Connector fit: the plug should seat firmly with no wobble. A loose fit causes intermittent charging and arcing.

Which laptops use it

The A20-240P1A / ADP-240EB BC supplies ASUS systems built to a 240W power budget, including select models in these families:

• ROG Strix series
• ROG Zephyrus series
• ROG Scar series
• TUF Gaming series
• Other ASUS gaming and creator laptops specifying 20V / 12A / 240W

Series names are a guide, not a guarantee — the same line ships with different power requirements across configurations, so confirm against your own adapter's label.

Before you order: a 60-second check

• Read your current adapter's label and confirm 20V and 12A (or the 240W total) — and that it says 20V, not 19.5V.
• Match either part number: A20-240P1A or ADP-240EB BC.
• Compare the plug shape and size to your laptop's port.
• Confirm the input reads 100–240V so it works anywhere you travel.
• If the original is lost, look up your exact laptop model in ASUS's spec sheet to confirm it requires 240W.