Thanks for your help! So... can I use 1B56h - 23h = 1B33h for the OEM7 module? English is my 3rd language. I think, I didn't understand something correctly.
No, you understood it right, it was my mistake not to mention that the length of the header is dependent on the length of the filename of the random data binary... When it fits then it fits, your calculation is right also............... We originally used the name OEMS.BIN therefore. 8 characters together. Then it fits. 1B56h-24h = 1B32h (6962)...name it OEMS.BIN and create it as OEM7 module. Get an untouched copy of your bios, extract the acpitbl module. Copy and write the created OEM7 module over the acpitbl module, modify your acpitable module (DSDT) and finally add it to the end using cbrom.... As always you may upload your final mod to check it....