External GPU (eGPU)

An eGPU is basically a box (enclosure) that contains:

• A desktop GPU (like NVIDIA/AMD)
• Power supply
• Cooling system
• Thunderbolt/USB4 connection to your computer

It connects via Thunderbolt (USB-C) and acts like an external graphics card.

How eGPU Works

Inside the enclosure, the GPU connects through a PCIe slot, just like in a desktop PC. The Thunderbolt connection transfers data between your laptop and the GPU by converting signals into PCIe data.

➡️ In simple terms:
Laptop → Thunderbolt cable → eGPU → Desktop-level graphics power

Key Features

• Plug-and-play (mostly) on modern systems
• Power delivery (can charge your laptop while connected)
• Extra ports (USB, Ethernet, etc. on some models)
• Upgradeable GPU (swap graphics cards anytime)
• Portable setup compared to desktops

Performance

• Typically 70–80% of desktop GPU performance
• Performance depends on:
  • CPU power
  • Thunderbolt bandwidth
  • Whether you use an external monitor