3.33 ghz

im going to be buying w7 upgrade disc.what im needing to know is what ill be able to upgrade on my pc after i install w7 from the rc disc? i already bought a neww hd .but ill probably like to buy a new cpu .i have a gigabyte p35 board w/ a pentium d 925 3.0 cpu .id like to get a 3.33 1333 c2duo...