Important when replace processor

When you will replace the processor unit, you must know FSB size for your motherboard. Because mistake selection will cause no boot PC. For example, your motherboard support with FSB 400 and you plug FSB 512 of processor, so i sure that your computer never boot.
On the physical of Processor you can see detail specification.
Next, also, you must know maximum range of your motherboard. For example if your motherboard support with pentium 4 2,8 ( maksimum range ), so you can replace the processor pentium 4 with 2,8 GHz ( maksimum ) only, or the processor with range less than 2,8. and so on

Be careful to replace the processor, if you broke the processor pin you can't repair it. or very difficult to repair it.