RTX 5090 DLSS 5 Tests Show a Power Delivery Bottleneck

Tom's Hardware has tested early DLSS 5 on the RTX 5090 and found that the flagship GPU's behavior changes sharply depending on power delivery. NVIDIA announced the technology's paper on September 4, and the publication's early checks suggest the single-connector RTX 5090 can run into a hardware limit before it runs out of compute headroom.

The tests covered Cyberpunk 2077, Hogwarts Legacy, and Control, with DLSS 5 injected through OptiScaler using a leaked library. That setup was meant to examine early behavior across different card designs, including the RTX 5090 Founders Edition and MSI RTX 5090 Lightning Z.

According to NVIDIA's paper, DLSS 5 takes about 8 ms per 4K frame, and Tom's Hardware said its results matched that estimate. The problem was not the timing itself, but how differently the two RTX 5090 versions handled the load once DLSS 5 was enabled.

The RTX 5090 Founders Edition, which uses one 12V-2x6 connector and a 575W limit, lost 42% to 49% of average frame rate with DLSS 5 turned on. The card repeatedly hit its 575W power cap and reduced chip clocks under load.

The MSI RTX 5090 Lightning Z, by contrast, has two 12V-2x6 connectors and a power limit of up to 1000W. With DLSS 5 enabled, it drew around 723W in Cyberpunk 2077 and around 720W in Hogwarts Legacy, while in Control it ranged from 691W to 802W.

Tom's Hardware's conclusion was blunt: the single-connector RTX 5090 appears hardware-limited for full DLSS 5 performance. For now, the test points to a flagship GPU that may be constrained less by raw power and more by the connector feeding it.

Is the RTX 5090 being held back by its power connector more than by its actual performance?