ASUS ASUS ROG Zephyrus G15 GA503QM (2021) Specifications
The ASUS ASUS ROG Zephyrus G15 GA503QM (2021) is a gaming laptop designed for enthusiasts seeking strong performance. This guide covers RAM, SSD, charger compatibility, and upgrade paths for this model. For a comprehensive overview of all ASUS upgradeable models, visit the ASUS Laptop Upgrades hub.
| Component | Specification |
|---|---|
| Processor | Ryzen 9 5900HS + RTX 3060 |
| RAM | DDR4, 0 slots (soldered) |
| Max RAM | 24GB (soldered + 1 slot) |
| Storage | M.2 2230 NVMe PCIe Gen3, 1 slot |
| Charger | 200W Barrel |
| Ports | 1x USB-C 3.2, 2x USB 3.2, 1x HDMI |
| Display | 15.6″ QHD IPS 165Hz |
| Weight | 1.9 kg (4.19 lbs) |
Memory Upgrade Path

The ASUS ROG Zephyrus G15 GA503QM has soldered DDR4 RAM (24GB (soldered + 1 slot)) which cannot be upgraded after purchase. Select the maximum RAM configuration when buying.
Important: Since the RAM is not user-replaceable, we recommend opting for at least 16GB at purchase to ensure adequate performance for years to come.
Storage Expansion

The ASUS ROG Zephyrus G15 GA503QM uses an M.2 2230 NVMe SSD with a NVMe PCIe Gen3 interface. The single M.2 slot supports drives up to 2TB.
Recommended M.2 2230 SSDs:
- WD SN740 2230 NVMe — Reliable compact SSD for the 2230 form factor.
- Samsung PM991a 2230 — High-performance OEM SSD in compact 2230 size.
- Kioxia BG5 2230 — Compact 2230 NVMe with good availability.
Note: M.2 2230 drives are less common than the standard 2280. Verify compatibility before purchasing.
Power Delivery & Charging
The ASUS ROG Zephyrus G15 GA503QM uses a 200W Barrel charger. This uses a proprietary barrel connector. Use the original charger or a compatible replacement rated for the same wattage.
Port & Docking Capabilities
Connectivity: 1x USB-C 3.2, 2x USB 3.2, 1x HDMI
A USB-C docking station like the Anker 577 USB-C Hub provides additional ports including HDMI, Ethernet, and USB-A.
Upgrade Difficulty & Tools Required
The ASUS ROG Zephyrus G15 GA503QM has a difficulty rating of 2/5 for upgrades (5 = easiest). The upgrade process is difficult — limited user-accessible components.
Tools needed:
- Phillips screwdriver (M2.5 or similar)
- Plastic spudger or pry tool (for bottom panel clips)
- ESD wrist strap (optional but recommended)
We recommend backing up your data and consulting the official service manual before opening the chassis.
Frequently Asked Questions
Can I upgrade the RAM in the ASUS ASUS ROG Zephyrus G15 GA503QM?
The ASUS ROG Zephyrus G15 GA503QM has soldered RAM (24GB (soldered + 1 slot)) which cannot be upgraded after purchase. Choose the maximum RAM when buying.
What is the maximum RAM for the ASUS ROG Zephyrus G15 GA503QM?
The ASUS ROG Zephyrus G15 GA503QM supports up to 24GB (soldered + 1 slot) of DDR4 memory.
What size SSD does the ASUS ROG Zephyrus G15 GA503QM use?
The ASUS ROG Zephyrus G15 GA503QM uses an M.2 2230 NVMe SSD. Make sure to purchase the correct form factor for compatibility.
What charger does the ASUS ROG Zephyrus G15 GA503QM need?
The ASUS ROG Zephyrus G15 GA503QM uses a 200W Barrel charger.
Is the ASUS ROG Zephyrus G15 GA503QM easy to upgrade?
The ASUS ROG Zephyrus G15 GA503QM has a difficulty rating of 2/5. Consider professional assistance for upgrades.
Recommended Products
These are the products we recommend based on this guide. All links go to Amazon UK where you can check current prices and availability.
| Product | Why We Recommend It | Amazon UK |
|---|---|---|
| WD SN740 2230 NVMe | Reliable compact SSD for the 2230 form factor. | View on Amazon UK |
| Samsung PM991a 2230 | High-performance OEM SSD in compact 2230 size. | View on Amazon UK |
| Kioxia BG5 2230 | Compact 2230 NVMe with good availability. | View on Amazon UK |
Prices and availability may vary. As an Amazon Associate, we earn from qualifying purchases.
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Helpful Guides
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Prices from PCHub.UK via ComputersDeal. As an affiliate, we may earn from qualifying purchases. Prices updated 2026-04-10 13:15:58.



