Planning partitions is part logic and part personal preferences. In some cases, partitioning is just a form of filing preferences.
I keep Windows and most-critical apps in my OS partition. I define critical as software firewall, resident AV scanner, resident anti-spyware scanner and resident anti-trojan apps. I keep the OS partition lean, since I image the OS partition weekly to DVD media.
Less-critical apps are installed in my APPS partition. I can't perceive any difference in startup time for program started from the APPS partition and apps started from the OS partition.
I keep all critical data on a dedicated DATA partition, which is imaged weekly to DVD media. Apps such as MS Word and MS Excel are configured to automatically save data files to folders on my DATA partition. I also save some backup copies of critical drivers and program-installs in the DATA partition.
Games are certainly not critical - I install them to a dedicated partion.
Other partitions, BACKUP for temporary isos, and DOWNLOAD for downloads are just personal preference for filing organization.
There are some other valid considerations, for example it's faster to defrag my 8GB OS partition prior to imaging than to defrag an entire single-partion HD.
I've never sensed any performance benefit for using a dedicated page-file partition - but that's almost a religious argument for some.
Edited by gud4u, 07 March 2005 - 11:29 AM.