as the title says i am upgrading my motherboard, last time i did this i just formatted my hdd and re installed windows, this time i would like to keep the data on my D partition. can I just format my c partition or will it make me format the whole drive?
Each partition can be formatted separately (this is the main reason most people set up partitions in the first place (that and to make back ups easier) - that said there are a couple considerations :
1.) A new format and install of windows will delete the registry entries so all programs will need to be reinstalled in order to work properly (ie. registry entries - config settings etc.)
2.) If using an OEM version of windows -- a new MOBO technically means the old license expires and you need to repurchase a new license ! (though calling MS might get a new activation code it is something to keep in mind as you may need to buy again !)
3.) WIndows 7 is actually much better at recovering from a move to new hardware without having to format and reinstall if you just run a repair installation instead of reformatting and reinstalling - Just boot from the install media the first time after swapping MOBO and run a repair installation (this forces windows to reexamine the components and install the needed drivers for the new hardware instead of using the old drivers and can in many cases work to change the hardware without the need to reinstall windows and all programs) NOTE: it will still deactivate the activation status requiring you to call MS to reactivate - and depending on what you tell them and the mood of the rep you talk to they may\may not provide you a new activation code ( Technically OEM versions die with the original MOBO and can only be reactivated if the old MOBO failed and a replacement with the same exact model is not viable) - in many cases MS is pretty relaxed on the implementation of this policy and reactivation by phone\computer assisted response will work but be prepared to talk to a rep and explain the situation or to repurchase a new license if needed.