Should I partition HDD?

Hi,

I'm building a new desktop system and have a nice new SATA II hard drive of
250GB.
My previous drive (IDE), which I am removing has two partitions. One
partition for the system and the other for all my photo, music, re-install
files, etc.

I have read somewhere that using a second partition on a hard drive effects
performance.

Question - Will I negatively effect the hard drive performance if I create a
second partition of around 80GB for my permanent files?

I want to use my old hard drive in an external enclosure but if that
suddenly decides not to work one day I will lose everything!!

Advice????

Thanks

Stu


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