[hm-one]

i purchased the lacie d2 160gb external HD for my powerbook last week mainly for final cut editing and backup purposes.

today i decided that i am going to return the d2 and instead purchase the d2 extreme 160 that supports fw800. fw400 is fast, but when i backed up 45 gigs worth of files and saw that it took 1 hr, I figured that shelling out the extra 30 bucks to get the transfer time cut if half was well worth it.

my question is how can i make sure that every bit of data is wiped out from the external so that the future user who buys it used from the apple store will not use some sophisticated software to retreive my personal info. (cc info, addresses, etc etc).

i know i'm being a bit paranoid, but i need to make sure.

[MaxGuru]

Adapted from Apple's Disk Utility help:

1. Connect the disk to your computer if it is an external disk.

2. Open Disk Utility and select the disk or volume in the list on the left (select the icon of the drive with the name that begins with the disk size, not the one below it with the name you chose for it).

3. Select the Erase Tab. Click Options to choose a more secure method of erasing the disk ("Zero all data" and/or "8 Way Random Write Format").

4. Click the Erase button.

[Tenacious Dyl]

Well F/w 800 has the "potential" to be 2 times faster, perhaps a little more or less... but don't get your hopes that high. My guess is taht you will notice speed gains in only some fields, and never more than a 50% speed gain in most cases.

[hm-one]

thanks for the replies. tenacious, that's very interesting. for simple data transfers i shouldn't get my hopes up to expect a doublerate in transfer speeds?

[Tenacious Dyl]

Correct... remember... potential speeds are always potential speeds.

For example... USB 2.0 is apparently capable of 480 megabits per second, where as firewire 400 is only 400 megabits per second. Yet in almost 99 out of a 100 trials on Macs, firewire is faster, for various reasons.

Just because firewire 800 is capable of 800 megabits per second doesn't mean it will go that fast. You computers software and drivers for the device might say only go up to 640. Also remember that every function of the hard-drive physically won't operate that fast. I do not know which, write, seek, read, etc. But I do know that some hard-drives are simply "slower" than 800 megabits a second.

Perhaps if you got a VERY fast (well over 10,000 rpm) harddrive, and put that in a firewire 800 enclosure, your speeds would be closer to double.

What you must look at is how "maxed out" are you. 400 vs 800 is bandwidth. If your everyday harddrive use rarely exceeds say, 310 megabits per second, then the 800 upgrade won't be noticable.

You can compare this to standard broadband being upgraded to t1.
Most websites you load with broadband you load at their speed with a newer mac. For example... I know if i were to buy a G5 with very fast everything, there would be a fair amount of webpages that wouldn't load any faster (noticably). Why? Because im already loading the webpages at the very speed their servers are capable of sending to me.

If you open small files, and do transfers only occasionally, and don't have an uber fast drive, i don't think that firewire 800 will be very noticable.

Also recollect that transfering data from say a 40 GB internal drive at 5400 or 7200 rpm to a really fast firewire 800 drive will still not be a fast transfer, because the 40 GB drive is your "low point" and lowering your speed.

So... to see true "max transfer" speeds... you would need to transfer data from one firewire 800 drive to another firewire 800 drive. I think you understand? I hope my english and my terminology makes sense.

Hope it helps,
Dylan

[tooki]

NO hard drive is fast enough to saturate FW800, so you won't see a doubling in performance.

The fastest drives out there, like a Seagate Cheetah 15K.3 on FibreChannel, have a maximum sustained speed below the 100MB/sec of FW800. In the case of the Cheetah, the maximum sustained speed is 86MB/sec (the minimum sustained speed is about 30MB/sec lower).

But FireWire drives use parallel ATA drives at 5400 or 7200 RPM, not 15,000 RPM FibreChannel drives. Let's look at some of the drives you might actually find in a FW enclosure:

Seagate's 7200.7 lists only an average sustained rate of 58MB/sec.

How about Hitachi's fastest, the 7K400: sustained speeds of 61.4-29.8MB/sec.

So most drives rarely saturate a FW400 bus, much less FW800. (Of course, when using multiple FW drives, having the extra throughput on the bus is most welcome.)

tooki

[hm-one]

thanks for all the usefull info. everything makes complete sense. essentially my HD is the bottleneck that will not handle the fw800's speed.

so here's what i have. i own a 17" pb 1.33 with the 4200rpm HD. i'm thinking that the d2 fw 800 external has to be at least somewhat faster than the fw400 version i currently have. so do you think the extra 30 bucks is worth it?

[tooki]

For just $30 extra, why the hell not?

Besides, when you outgrow that drive, then you can replace its drive mechanism with a newer, faster one, which might well take better advantage of the FW800 speed.

tooki