Do I need to reformat a partitioned HD after upgrades?

My question deals with reformating my entire partitioned hard drive after I have upgraded components on my PC.

I have a 3 partitioned hard drive at the moment. It has one drive for just windows stuff and utility software(Firewall, spyware, antivirus, diskeeper...). Then one for just music and documents and a third for Games and their files.

I have upgraded my:
Motherboard to an entirely new chipset(Nforce4)
Processor(3700+)
Ram to a new type(DDR 400) and size(2gb)
GPU(7800GT)
PSU(520w)

I plan to reuse my current HD but I am unsure as to how it will function with all these new parts if I don't reformat the entire hard drive and re-partition and reinstall everthing.

In a perfect situation I would only need to reformat my Windows drive and reinstall the utilities. With that I would not have to lose all my music(way to much to backup to something else 25gb) and games. I am just unsure if this will effect the performance of my games though.

(Best Option) -- So I know I will have to at the very least I will need to reformat my Windows partition?


(Okay Option) -- Reformat the Windows partition and the games partition for clean reinstalls, but leave the music/docs partition alone?

(Least desired option) -- Reformat the entire thing?

Thanks,
Kyle