What will i have to do when i boot up my pc with replaced parts



For best results re-install Windows. Depending on what type of Windows license you have, you might have to buy a new copy. However, if you have a retail copy, you should be fine. If OEM, you will probably have to call Microsoft to help activate it. If this was on a OEM machine (built by HP, Dell, etc.) you will need a new license. Regardless of license type, if the parts were replaced due to failure, Microsoft will probably help you activate it.