congrats bro, finally your wait is over..
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for partitioning, i would either recommend easeus or a much better solution, clean install of windows, formatting and creating partitions while installing windows..
and dude, 40GB is too low, atleast give it a 100GB for C:, after installing just win8 and drivers, my C: was already 30GB full, and now after installing all softs (no games and other stuff, just softs), it's eating ~60GB, so give it atleast 100GB, as you also need 10GB of min. free space everytime in C: for windows to function smoothly..
And logical and primary drives:
Primary: Cannot exceed four, if you want to dual boot or install multiple OS's on different drives, then to install an OS on a drive, it has to be a primary partition..
Logical: Can be as many (extended) as you want..
After installing windows8, you would definitely notice more fluidity and responsiveness from your system, don't worry about that..
Product key and product id are two different things, so don't worry about that, you'll need product key (not id) while installing windows and you are'nt having product key on lappy??
Have you checked inside the battery compartment???
And that's a very good thing that you got the GPU logo with corei7 logo, old users like me were'nt that lucky to get a Radeon sticker..
I think you would have got the windows 8 driver disc, in that case there is no use of downloading drivers from Dell website as for now, as Dell has'nt launched any updates for any of the Win8 drivers since their launch, but it's better to download and keep them as backup..