treid this one sins that was the right brand did not work B. If the last 4 letters of the Service Tag of your Dell laptop isn't 595B/D35B/2A7B/A95B (like 1F5A/3A7B/3A5B/1D3B etc.) 1. You may try to do a forceful BIOS recovery. Read and search the forums for instructions. Some useful links are below. 2. You may whose last 4 letters of the Service Tag is 595B/D35B/2A7B/A95B. Then follow Section A.