Product Activation

I have got a Windows XP Pro CD from my school, it is a
licensed one which is subject to MSND-AA. Microsoft
authorized my university (University of Waterloo) to
distribute it to its students.

The problem I have is I installed Windows XP on my laptop
around 6 months ago, and after about a week or two, my
laptop didn't work anymore, I haven't fixed it till now,
because it was already out of warranty, and it would cost
a lot to replace a new motherboard for it. So I decided to
give it up and I eventually bought a new desktop. Then I
asked for the Windows XP Pro CD from school again, and
installed it on my desktop. When I tried to activate it
with my previous CD-Key, it said I couldn't activate it
more than once. I asked the staff at school and also
checked the website regarding XP activation, I knew I
could only install it on one computer. The thing is my
laptop doesn't work anymore, and I won't use it and will
probably throw it away, but so can I install the Windows
XP on my new desktop then? Shall I call microsoft to deal
with it?