Since I couldn't find a working software that overclocked my card at startup beyond CCC limits, I came up with Ghetto solution using AMDGPUTool, a .bat file and the Windows Startup folder.

1 - Download latest AMDGPUClockTool and extract to a folder.

2 - Open notepad and paste the lines below, editing AMDGPUClockTool folder and the desired clocks (GPU, Memory). Save it with a name.bat.

start D:\AMDGPUClockTool\amdgpuclocktool.exe -I=0 -ENG=875 -MEM=1000 &
start D:\AMDGPUClockTool\amdgpuclocktool.exe -I=1 -ENG=875 -MEM=1000 &
3 - Copy or Move the name.bat file to the folder:

C:\Users\User Name\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup


DONE!!!

Every time Windows is started, the clocks will be applied automatically.

For those who have 2x 3870x2, two more lines should be included in the .bat file, changing only the -I parameter to =2 and =3.

This tip works with all AMDGPUClockTool supported cards.

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