Hard drive and FCP question

Question

I got lots of short questions and a semi bigger one.
I plan on editing HD and standard definition video with my iMac using FCP. My hard drive is 130 gig and I need a bigger one. My current fire wire ports on my iMac are both 400mb/sec and that is too slow for HD and I was told I cannot get that upgraded. The guy at an apple store told me iMac's use lap top hard drives and there is no big improvement from my current 130 gig.
I looked my hard drive up and I believe it is actually a desktop hard drive if I'm not mistaken. The model number is ST3160812AS. So does that mean I can get a desk top hard drive upgrade? If so I was looking at the Hitachi Deskstar 7K1000 750g 7200 rpm. Is that a good choice?
How do you upgrade to a new hard drive anyway? Who installs it? Me or can I get a professional to do it for me for a small fee? How do I get all the current data on my hard drive on to the new one?
Where I usually do most of my editing the computers have two hard drives. One to hold the footage and transfer the data to the other one which is actually doing the editing. My film teacher says this is the best thing to do, but obviously I can't do that since two hard drives in my iMac is out of the question and I can't get a fire wire port fast enough to support a hard drive that isn't just for storage. Can that hard drive I was looking at handle doing the two processes on its own? Do I have any other options?
Thanks in advanced.

Answer 1

J D McIninch wrote:
\- The bitrate for HDV high-definition video is *25 Mbps* -- 1/16th the bandwidth of FW400.
\- Max bitrate for AVCHD is *24 Mbps*.
\- DVCPRO100 has the highest bitrate of all the HD video formats at a whopping *100 Mbps*.
The maximum burst speed of FW400 is about 393 MBps \[typo: 393 Mbps\] and sustained
transfer rate it near that.
You shouldn't worry about the transfer rates on FireWire as much as the drives.
Most hard drives are not going to be able to sustain transfer rates of 100 Mbps --
you probably need an array for that. It's moot, however, if you are using consumer-grade
HD (with rates around 25 Mbps).
Very useful info on the video data rates on various formats, JDM -- thanks.
However, I'm a little confused by the disk drive data rates you quoted. It appears that
the numbers you mentioned are actually MBytes/s (MBps) rather than Mbits/s (Mbps).
The OP's current internal HD (ST3160812AS) is a 160GB Seagate 7200.9 family drive
spec'd at 83MBytes/s max sustained throughput. (That applies only to the outermost
tracks, when the drive is nearly empty. It'll be about 40MBytes/s on the inner tracks.
So, when nearly full, the internal drive is about the same speed as a FW400 external.
The 750GB Hitachi Deskstar 7K1000 is slightly faster (ca. 85-90MBytes/s maximum,
when empty, and half of that when nearly full). That's fairly fast as today's large HDs
go, but not quite as fast as the new Seagate 7200.11 family drives (105MBytes/s max)
or WesternDigital's WD7500AAKS (98MBytes/s, max) -- but they're all more than fast
enough to saturate a FW400 link, even when the external drive is nearly full.
BTW, from the spec sheets, I see no indication that any of the four drives mentioned
here are "green." They all have similar power requirements; if anything, the Hitachi
consumes the most power, and the Western Digital the least. (That seems to agree
with tomshardware.com's observation 7K1000 drives run hotter than most others.)
It is nice to see that today's fastest 750GB drives consume no more power than the
best-performing 160GB drives of a few years ago.
vtwiz wrote:
Don't attempt to replace the drive in your iMac. Keept it for the OS and software
and use an external drive for all your video.
Good advice! Regardless of the size of your internal drive, save the data-flogging
for the easily-replaceable external drive.
Looby