To partition or not to partition?

My new (to me) iMac is great. Everything I have wanted to do so far is working fine; all my photos, movies, documents, and music are transferred over (I think, make one last check tonight). I have VLC and Vuze downloaded (Vuze runs my movies to my xbox over my network), and am still looking for free apps that I want/need.

Now to the backing up part of having ~16 days of music, and 7K photos.

I have a Free Agent Seagate 1tb external via USB, but have the FireWire 400 option, and an Airport Extreme Base Station coming in the mail. Couple questions.

1. I want to limit desk clutter, so I have concluded that backing up via FireWire (still need to purchase the cable) would be silly since I have already done the heavy transfer (PC files to iMac first time). And the only other heavy transfer would be the original backup. I'm guessing around 350-400gb.
UNLESS-—•
Buying the FireWire cable will give my external power. I can handle the single cable from the iMac to the external. Will it draw power from the iMac to the Seagate?

2. Should I partition the external? With it being 1TB and my HD being 500gb, should I make X#GB on the external for Time Machine? And the rest, Y#GB for what? Anything I do not want backed up? That seems counter intuitive to having an external drive.

3. If I partition the drive it needs formatted. Understood. Are the partitions different format types? How much of that will i do on my own? How much will TM do for me?

I think that's all I needed answered.
Thanks
Tt

power all depends on the external you buy, some are bus powered, some are mains.

formatting the HD:

depends on what you want it for. TM will want HFS+ (Mac compatible.)

for your non-Time machine partition, you could go with HFS or FAT32. fat 32 would be good if you do any work with windows, as OSX & windows can write to it. HFS can be read by windows but not wrote, and NTFS is r/w in windows, but read only in OSX.

they always say you should have a backup drive twice the size of your computer's internal.

Ok. I think I get it.
TM wants the Mac standard.
I don't intend to run windows anytime soon. I guess I could opt for the fat32.


So how do I partition? Will TM ask me if I want to?
If not, where/how do I do it?
How do I format the second partition to fat32?

Before you do any partitioning......

Time Machine does not require a separate partition as it can nicely exist along with other data provided the drive is formatted to HFS+.

Keep in mind that if you partition and format the second partition as FAT-32, you will be limited to a single file size of ~4 GB. If you intend to have large videos or music files that exceed that size, you will be unable to store them to the FAT-32 partition.

You stated that you don't intend to run Windows. I would then leave the drive as one partition formatted to HFS+.

Thanks chscag. I did not know that about fat 32.
I guess i could always do it later. The formatting that is.

I still wonder if it will draw power from the IMac. Trial and error I guess. I'll try it tonight.

drawing power from the computer (bus-powered) is dependant on what external you buy. most generally aren't.

The Seagate "Expansion" series are (well, up to 320GB i think) and ive been using them for quite a while now, very durable.

http://www.seagate.com/www/en-gb/products/external/expansion/expansion_portable/