External Hard Drive for iMac - Firewire or USB?

Hi Janice, in short, FireWire drives are faster than USB, in terms of transfer speed, and FireWire 800 is much faster than FW400. We shall not get into the details of how many megabits per second data is transfer.

But personally, and preferably if you intend to use your external disk as a Time Machine Backup drive which requires constant on and constant back up, I would go for FW800.

If you live in the States, OWC is quite a good brand in terms of external drives and enclosures, I believe you are able to buy them online?

I myself use a Maxtor One-Touch FW800 1TB Drive, which is quite good.

Well, external hard drives in a way work like a zip drive, if you want to unmount them you still need to drag their icons into the Trash; These external drives nowadays have bigger capacity (up to 1TB or more) and are even more economical to get.

Cheers

Janice Fisher wrote:

Can you clarify the difference between a firewall \[sic\] connection and a USB connection?

\- USB is truly universal -- it can be used to transfer stuff between PCs and Macs.

\- Firewire is (mostly) an Apple thang; it's faster than USB and works well with Macs.

\- Most firewire-capable external drives also have USB -- that's the best way to go.

I assume you use one or the other, but not both.

You can only use one at a time -- but can quickly swap from one to the other.

Also, some USB hard drives require 2 USB ports; this I do not want!

That's true for some small "bus-powered" USB drives. They're handy for road warriors
who must tote multi-GB in a brief case, but they're a poor choice for general desktop
use -- because they're slow, less reliable than a "regular size" drive, and about twice
as expensive (per GB).

You didn't mention what you plan to do with the external drive (backups, music/photo
collections, video editing, etc.), how much disk space you expect to need, which iMac
model you have, or what price range you have in mind. It would be difficult to make a
specific recommendation without more information.

Also, do these hard drives work like a zip drive.....no more complicated?

Less complicated. There are no Zip disks to fiddle with -- just plug it in.

Looby

Hi Janice

Get on your reading glasses, because your going to get a lot of information.

1. Briefly scan the section "USB compared with FireWire" in the link below:

http://en.wikipedia.org/wiki/Usb#USBcompared_withFireWire

2. I suggest using a FireWire External HD for the simple fact that it leaves the USB bus open for your other devices (iPod, camera, cardreader, flash/zip drives, printer etc..) and you will encounter little or no conflicts with those other devices.

3. Now the hard part yes they pretty much work in the same fashion as the flash/zip Drive. If you are considering an External HD for TimeMachine or a Bootable drive, here are a couple of article's that are a must. It is very important to have the External HD formatted & partitioned properly for use with TimeMachine and or Bootable. note: partition "GUID Partition Table" and format "Mac OS Extended (Journaled)" and Ken Stone does a great job of explaining that in the following article:

http://www.kenstone.net/fcphomepage/partitioningtiger.html

and then here is Apple's TimeMachine Support page:

http://www.apple.com/support/leopard/timemachine/

4. This OWC Mercury Elite Pro link is a great place to start shopping! They offer a wide range of sizes and configurations that you won't find at your local PC/ USB only electronics retailer. The best configuration for you would be the FireWire 800/400+ USB 2.0 models, your iMac supports the faster 800:

http://eshop.macsales.com/shop/firewire/1394/USB/EliteAL/800/

Also have a look at the LaCie:

http://computers.pricegrabber.com/hard-drives/lacie/p/11/st=filter

I have probably created more questions than answered, but I also know there are lots of great folks here in the forum ready to help out.

Dennis

Yes most newer drives come formatted MS-DOS (FAT 32) and you can just copy your files to it same as your zip drive.

The drive will be pre-formatted when you get it and theoretically you could use it right out of the box. However it's a good idea to check the format of the drive before you start using it. Often USB external drives will come pre-formatted for PC-DOS format and unless you plan on using that drive on a PC, I would recommend reformatting it Mac OS Extended(Journaled). OTOH most Firewire drives will be pre-formatted Mac OS Extended anyway which is what you want.

If you need to format the drive or one way to take a look at the drive format is to open up Applications/Utilities/Disk Utility. Click the drive on the left hand side and read the details at the bottom. Should look something like this:

http://ftp.georgetek.com/George/DiskUtilMS-DOS.png
http://ftp.georgetek.com/George/DiskUtil_Mac_OSExtended.png

George

There is no question that for general purpose and for booting, FireWire is the way to go. If you intend to boot with it or if you intend to use it with Time Machine, get FireWire 800 if you can afford it. Today it is typical to see drives with FireWire and USB so you get the best of both worlds there. If you come up against a machine that can only do USB it will be compatible. FireWire 800 drives will be more expensive than FireWire 400 but the speed boost is impressive.

If you are budget constrained and if you will use the drive only for iTunes, USB is acceptable. Otherwise, FW!

It's "FireWire" BTW.

A Time Machine drive needs to have a large capacity to be effective. 120GB is not that large; your iMac internal drive is probably bigger. Since an iMac is a desktop Mac, I would get a desktop external drive that uses a 3.5-inch hard drive mechanism. A 500 GB 3.5-inch drive costs about the same as a 120 GB 2.5-inch drive. 500 GB would be about the right size to use as a Time Machine drive.

Note: You can use it for other things at the same time the drive is being used by Time Machine.

I think you are starting to put the cart before the horse. Back up (pun intended) and think about what your goal is. Is it your intention to back up just your user documents, photos, and music? When disaster strikes (note that I didn't say if) are you okay with installing the OS from the DVD, reinstalling all your software, reconfiguring your printer, your scanner, your internet, and setting everything up the way it was? Notice that I'm really piling it on here! I don't know about you, but it took me about a week to fully move into my new computer and if my hard drive died tomorrow, I don't want to spend (I don't have) a week putting it back together again.

My backup plan, in the nutshell, consists of three parts. 1) a clone of my hard drive; an exact duplicate so if my drive dies I can reboot and get right back to work. So that when I install the new drive I can immediately repopulate it as it was. 2) an incremental backup, especially of my data. If I discover I deleted a file I didn't mean to, I can go back a few days to a pre-delete backup and restore that file. 3) a backup of crucial material that leaves the house so if file destroys my computer or a thief makes off it with I haven't lost the most very precious information.

I believe everyone should adopt a plan similar to mine. The particulars of how you achieve the plan will vary but I think all three steps are vital. If you agree then your hard drive needs to be large - 120GB probably doesn't come close to cutting it. To estimate how big a drive you'd need to implement this plan, determine how much of your drive you are currently using. Double it. That is once for the clone and once for the complete (non-bootable) backup Time Machine will make. Now, at the very least, add the full contents again. That is for a couple weeks worth of incremental backups. Now add another 50% for growth as you add new programs, music, photos, and data.

So if you are currently using 30GB of your computer's hard drive, 105GB is the very smallest drive you want. The 120GB drive you are talking about is okay. Barely. When you get it make a 40GB partition and a 80GB partition. The 40GB is for the clone you'll make using SuperDuper! and the 80GB is for Time Machine. Of course, if you are using more than 30GB then you need a bigger drive for your backup. And if you know you intend to add a goodly amount of stuff to your drive soon, then plan for it now.

Now if you are okay with getting the computer back together more slowly - maybe being without it complete if the drive dies - you can dispense with keeping the clone. In that case, you will want to determine your current disk usage and buy a drive about 150% to 200% of that. It'll take about an hour to reinstall the OS on the hard drive and depending on how much you have in data and other programs, another half hour to a couple hours to restore that.

It does not have to be 500 GB. But if you want Time Machine to serve its intended purpose (let you retrieve a file you deleted last year), then it needs to be several times larger than the storage you are backing up.

I like this drive

http://eshop.macsales.com/item-specials/Newer%20Technology/MS2F7500G16/

It has FireWire 400, USB 2.0 and does double-duty as a FireWire hub and USB hub.

My test at home and work (my wife and office mate are two of my guinea pigs) would seem to indicate that your TM drive should be, at a bare minimum 150% of the current usage of your drive and this allows for no growth which could be a problem for many of us. My wife is at that 150% mark and she has about 2 weeks of backups but as she continues to rip more music and add more photos she's clearly going to want/need a larger drive. Meanwhile my office mate's first backup was in the first week of February and his TM drive use is now just over 250% of his internal hard drive usage (minus some files he's excluded.)

So while I suggest a bare minimum of 150% I really do urge people to consider 250% to be the minimum. Me? I'm backing up about 50-60GB of data on my desktop and I have a 1TB drive for TM. I don't take chances.