Step 1: Update the BIOS
Before you remove your first screw, it is critical that you upgrade your BIOS to the latest version. Manufacturers often update BIOSes to allow support for newer CPUs. If you upgrade to a chip that's newer than your BIOS allows, your notebook won't boot at all. Check the support section of your manufacturer's Web site for any BIOS updates for your notebook.
The process for upgrading your CPU is usually almost identical to that for upgrading your graphics board. In the case of the Inspiron E1505, the CPU resides directly underneath the video card assembly
, so disassembly instructions are exactly the same for this part as for that one.