The AMD/ATI Pixel Clock Patcher tool by ToastyX has been available for quite some time wit the main goal of modifying the AMD/ATI video driver to allow higher resolutions and refresh rates by removing the 165 MHz pixel clock limit for single-link DVI and HDMI, the 330 MHz limit for dual-link DVI, and the 400 MHz limit for VGA. A more recent feature that is useful for everyone mining with ATI/AMD GPUs that have a flashed modified BIOS is the ability of the tool to also patch the video drivers to remove the BIOS signature check. With an AMD/ATI GPU thah has a modified BIOS (optimized memory settings for better performance or specific GPU/VRAM operating frequencies preset) normally the video driver will not work properly, so you need to patch it in order for the GPUs to be able to work normally and mine.
There are other solutions available to override the BIOS signature check, but using the AMD/ATI Pixel Clock Patcher tool is by far the simplest. The current latest version 1.4.7 is compatible with Catalyst 11.9 to Adrenalin 19.9.2, though iIt can be used with future versions if it finds the limits you need. All you need to do after you install the AMD video driver is to download the tool and run “atikmdag-patcher.exe”, then just reboot and you will be ready. Since the tool modifies a couple of things if you only need to remove the BIOS signature check you can rename the executable file to “atikmdag-patcher-bios.exe” and no other things will be affected than the BIOS check. After installing new GPUs or new drivers you will need to run the patcher tool once more in order to make everything work properly again.