hi guys

I was having a conversation with someone and they explained to me that with MS there is a disclaimer that if you purchase a new motherboard you have to buy a new copy of windows? Sounds abit absured to me. Anyway if this is true, when I get my new MB how will i go about installing windows and doing microsoft updates. A cracked version someone mentioned. I have copied an original SP2 windows Proffessional and I use my own cd key i found about three years back. I cannot remember if I activated it. Will I just be able to install windows and update as normal or will I run into problems with updating off the website. Any help will be appreciated.