MSI's GeForce RTX 5090 Lightning Z, priced at $5,090, is designed for extreme overclocking.
YouTuber Alva Jonathan recently pushed the limits of MSI's GeForce RTX 5090 Lightning Z, achieving a benchmark record with the card. However, this ambitious experiment concluded unexpectedly when an aggressive BIOS and thermal imbalance led to the GPU core cracking during the process.
Development & Initial Testing
Jonathan's involvement with the RTX 5090 Lightning Z began early, consulting on its development starting in August 2025. He received initial PCB samples and retail units for testing. Initially, he utilized a custom cooling solution before transitioning to the more extreme liquid nitrogen (LN2) method to achieve maximum performance.
Designed for Extremes: Card Specifications
The Lightning Z is purpose-built for competitive overclocking, featuring several key design elements:
- Dual 12V-2x6 power connectors, ensuring robust power delivery.
- An impressive up to 1,000W total power limit, signaling its high-performance intent.
- A sophisticated 40-phase Voltage Regulator Module (VRM) for stable power management.
- A dedicated 2,500W XOC BIOS, offering extreme overclocking profiles.
- An integrated 8-inch display for real-time telemetry, vital for monitoring during intense sessions.
Early Overclocking Performance
Jonathan commenced his overclocking journey with an initial setting of 3.25 GHz at 1.05V, observing the card drawing over 700W. In the demanding 3DMark Port Royal benchmark, the Lightning Z scored 43,112 points with an 800W power limit, a significant achievement that exceeded scores from other RTX 5090 models. Peak power consumption during this particular run reached 772W.
Pushing Limits with Liquid Nitrogen (LN2)
For the most extreme tests, Jonathan collaborated with ARX (arxidmedia) for liquid nitrogen cooling. Maintaining a stable operating temperature proved challenging; despite the heatsink reaching -40°C, the GPU itself climbed to 9°C under load. At 1.12V and 3.42 GHz, power consumption soared, exceeding 1,000W. The team noted that the safe operating range under LN2 appeared to be between 0°C and 15°C, with system crashes consistently occurring at 21°C.
Setting a New World Record
During GPUPI testing, a brief peak of 3.6 GHz was observed around 0°C. The team ultimately stabilized the card at 3.5 GHz and successfully set a new HWBot world record for GPU compute performance in Geekbench 5, achieving an remarkable score of 683,433 points.
This record remains unbroken.
The Unforeseen Core Failure
The ultimate failure of the GPU occurred when the team switched to an earlier revision of the 2,500W XOC BIOS. This BIOS reportedly applied voltage too rapidly. At a critical point of 1.2V, the GPU core visibly cracked. This catastrophic event is likely attributable to thermal shock from an extreme temperature imbalance across the die.
The incident resulted in an approximate loss of $5,000, though other board components remained functional.
Future Endeavors
Despite the setback, Jonathan plans further testing with four additional samples of the RTX 5090 Lightning Z. He intends to improve cooler mounting techniques and may opt for a more stable retail BIOS for future attempts. Other ambitious targets, such as scores in 3DMark Solar Bay Extreme, were not achieved in this initial groundbreaking run.