Developers bypass vbios restrictions on Nvidia GPUs with new flash tools

Several software engineers have found a way to bypass Nvidia’s GPU BIOS restrictions. In many cases, this allows users to flash modified vBIOS versions on their video card. Since the GTX 900 series, Nvidia GPUs have had a security processor that prevents this.

Two different developers, Veii and Kefinator, have created new tools that allow users to flash the bios of their Nvidia GPU. That writes TechPowerUp on Monday. With the tools it is possible to flash ‘almost all’ vBIOS versions on almost all Nvidia GeForce video cards. This bypasses the security functions of Nvidia’s Falcon security processor.

The tool makes it possible, among other things, to flash the BIOS of a GPU with factory overclock on a cheaper variant of that GPU with lower clock speeds. For Nvidia’s Turing GPUs in the RTX 20 series and older chips, the signature check can even be completely bypassed. This makes it possible, for example, to increase the current limits. Without a signature check it is also possible to create custom BIOS versions with different voltages, fan curves and thermal limits.

For newer video cards in the RTX 30 and 40 series, there are more limited crossflash options. Users can flash other vbios versions on their GPU, but cannot manually adjust the bios themselves. For example, users can restore the former standard voltage of 1.10V on a GeForce RTX 4090. On newer RTX 4090 models, the voltage is limited to 1.07V.

The tools from Veii and Kefinator, respectively OMGVflash and NVflashk, are available for free. However, flashing a vbios is not without risks and voids the warranty of video cards; It is therefore mainly intended for power users. It is recommended to make a backup of the existing vbios beforehand. Both tools have an option to save the default vbios; GPU-Z can do that too.