HP 4720s - after modding bios (new post Logo) laptop goes black screen

[Hgi]

Hi friends,

i have one problem. I am learning modified bios on my HP 4720s and i am using UEFITool. I have external flash programmer for eeprom, when i readed eeprom on the motherboard and this dump i have modded by UEFITool, then i wrote new modded bios to motherboard eeprom. I am laptop turn up, my laptop goes black screen and i dont know, what i do it wrong. My first project is change post Logo HP.

I am use UEFITool and edit it the original bios dump, i am search when is logo -> extract body ->  replace body with new logo ... and save image.

Can you help me any body PLEASE, what I am doing wrong? I am very apologize for my English. I add to attachment my original bios dump, and my modded bios dump for HP 4720s.


Thank you very much for your help.

[Hgi]

nobody help me please? I cant find, where is problem

[genius239]

I think your logo replace was right ,i have spend many time to find any others possible hp image on bios ,but i got a failure .
So , i think there are some lock or limit with custom logo.

Could you tell me ,bios menu is "Security" ,"System Configuration" ,"File" ,is it??
If it is ,could you capture a screen with System Configuration?

As i found some logo limits string on "System Configuration" ,like "Custom Logo" .