I trying to modify Phoenix BIOS for Lenovo G550 v2.55 (18CN46WW) from this post: /threads/5866-LENOVO-(IBM)-Bioses-especially-Thinkpad.?p=384982&viewfull=1#post384982 I want to change logo but all my attempts to do this ends with fail. At first I took Phoenix BIOS Editor (18.104.22.168 version) and try to rebuild BIOS without any changes and builded BIOS was quiet different from original (I used Total Commander in binary mode to compare). So I decided not use this tool to modifying BIOS. Then I downloaded Phoenix Mod Tool v1.84 from this thread /threads/13194-Tool-to-Insert-Replace-SLIC-in-Phoenix-Insyde-Dell-EFI-BIOSes?highlight=Phoenix+Mod+Tool In Advanced options I unchecked all options, that modify BIOS and checked options "Allow user modifications of modules", "Allow user to modify other modules" and "No SLIC". After that, I pressed "Go" and BIOS successfully recompiled without any changes (I compared it with TC and they completely match). Then, I extracted original Lenovo logos with Phoenix BIOS Editor from LOGO01.BIN and LOGO02.BIN modules, checked sizes and create new bmp's 8 bit color depth with same size but another resolution (352x254, when original was 740x126). I imported them in Phoenix BIOS Editor in Splash Screen editor, press Build BIOS, but didn't save it. From "TEMP" folder in Phoenix BIOS Editor I copied modified LOGO01.BIN and LOGO02.BIN files, then, I run Phoenix Mod Tool, when it prompted me to change files in "DUMP" folder I replaced original LOGO01.BIN and LOGO02.BIN with modified files and pressed OK, BIOS successfully builded. I compared it with original BIOS with TC and there was only 4 places that were different. I would even say that there were 2 places and there were 4 bytes at addressee 0x12ddc8 that were 65 A5 74 19 were replaced in modified BIOS by C1 3C 1B 16 then there were 18 bytes that was same in both bioses, and 2 bytes that were 5C 19 in original, 03 16 in modified, then 2 same bytes, again two different that were 50 19 in original, F7 15 in modified, 2 same bytes and then there was large massive of bytes that perhaps was properly logo in compressed form. And with offset 0x5C2F from 0x12ddc8 (23,599 bytes) there were block with same differences (just different bytes, structure of differences that I described below was same), I think that was second logo that I replaced. So, when I flashed BIOS with WinCris (it's one way of flashing that I truly trust) notebook didn't load. I recovered original modified BIOS (from /threads/5866-LENOVO-(IBM)-Bioses-especially-Thinkpad.?p=384982&viewfull=1#post384982) again with WinCris and so here I am.