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For reference, here are the mean power, clock, temperature, and noise results for the RTX 5090 Founders Edition and RTX 5090 Lightning Z.
We’ve broken our overall power charts out into three separate means so that you can see the effects of enabling path tracing on power draw compared to lighter RT and raster titles.
These summary results also demonstrate the superior performance of MSI’s liquid cooling system. Even with 25-30% more power to dissipate as heat, the Lightning Z heatsink keeps the GB202 chip as much as 16 °C cooler than the Founders Edition. That’s expected given that the FE card is using a much smaller air cooler, but it’s impressive nonetheless.
Next up is noise testing. We measure noise at a distance of one meter from the system under test using a calibrated Triplett SLM400 meter on a sturdy tripod. The noise floor of our testing environment, as measured by this meter, is 32.6 dBA.
For all its other advantages over the RTX 5090 Founders Edition, the Lightning Z’s cooling system isn’t quieter. But given that it’s dissipating anywhere from 25% to 30% more power as heat than the FE card, the fact that it’s just 1 dBA or so louder is an impressive result.
That said, the Lightning Z’s liquid cooler has more moving parts than the Founders Edition’s twin fans, and the liquid cooling pump within is especially noticeable on the bench. At full tilt, it has a highly tonal and even somewhat growly or rattly quality that suggests it’s hard at work. The three fans on the 360-mm radiator are pleasant under load, though.
Coil whine is another noise source of concern from graphics cards, and the Lightning Z’s 40-phase VRM does still exhibit some whine. Compared to the extremely prominent and complex whine of the Founders Edition card, however, the Lightning Z is far better controlled in this regard.
