Asus Zephyrus Duo 16 GPU Upgrade

I need my Asus ROG Zephyrus Duo 16 to run an NVIDIA RTX 5090. The laptop currently carries its stock GPU, so the task involves a full board-level graphics card swap (or compatible MXM/embedded solution), BIOS or vBIOS modding if necessary, and any hardware tweaks that ensure the new card is recognised and performs at desktop-class speeds in demanding games.

Because the RTX 5090 will push the thermal envelope, I also want the cooling system overhauled. I will supply or reimburse for premium thermal paste, and I’m happy to integrate a custom liquid cooling loop as long as the final build remains reasonably portable (external radiator solutions are fine).

Scope of work
• Source or fabricate a fit-for-purpose RTX 5090 module and any required adapters.
• Modify the motherboard, heatsink, or chassis as needed so the card seats securely and clears all components.
• Flash/patch BIOS so the laptop posts and boots with the new GPU without error codes.
• Install improved thermal paste on CPU and GPU, plus design and fit the liquid cooling system.
• Stress-test the machine (3DMark, Time Spy, Cyberpunk 2077 at 4K) for stability and temperature.

Acceptance criteria
– RTX 5090 detected in Device Manager and GPU-Z, running at full PCIe speeds.
– Sustained GPU temperature below 80 °C under 100 % gaming load for 30 minutes.
– Minimum 30 % FPS uplift over stock configuration in the test titles above.
– Chassis and ports fully functional; keyboard and second screen remain intact.

Please outline your experience with laptop GPU swaps or similar high-end mods, the tools you’ll use (reflow station, hot air, custom loop parts, etc.), and a realistic timeline for parts acquisition, fabrication, and testing.