J. Clarke said:
I'm not even going to _try_ to respond to the mess below.
simply because you *KNOW* you are arguing the wrong side of this argument.
However you have some serious misconceptions about Macs, about PCs, about
Firewire, about SCSI, and much else.
and your misconceptions come from what? intuition?
your own statements indicate that you do not own, a Mac - so do you have
any real life experience with them? or are all of your misconceptions
based on intuition?
- hot swappable -
firewire devices are hot swappable, plug/unplug the connection cable(s)
as needed. This is "not recommended" with scsi - ie blow a controller.
I am specifically referring to devices, entire drives - enclosure
included, NOT bare drives in specially constructed bays inside an enclosure.
- Device identification -
firewire requires no user intervention to set ids on connected devices.
No jumpers, no switches.
- connection limits -
scsi is relatively limited in the number of devices that a single chain
will support. 7 devices in scsi 1, & 2. 16 n latter versions. Firewire
can support 64 devices.
- performance -
Firewire 800, has a performance level of up to 100MegaBytes/sec.
true the fastest scsi can claim a higher theoretical rate.
BUT - with the possible exception of the fastest scsi RAIDs, actually
filling and sustaining these data throughput rates (firewire or scsi) is
difficult.
And sustaining these (100+ MB/sec) throughput rates for a single drive i
impossible with todays hardware. Even an 8meg cache drive can only
burst feed a LVD320 scsi connection for 1/40 sec. After this short time
the throughput limit of either Firewire or scsi is limited by the
drive's physical response time - which is significantly slower than
100MB/sec.
- Cost -
Firewire - is cheaper (period).
Scsi drives are more expensive than IDE drives with average pricing
starting at $1/gig and going up as the drive capacity increases. a
180gig scsi drive costs $653, more than $3.50/gig (lowest listed price
on pricewatch). A 320 gig IDE drive lists at $291, about $0.91/gig.
That is nearly twice the capacity (180g vs 320g), at less than 50% of
the cost ($653 vs $291). I can almost buy an 8 drive firewire enclosure
($382 -
www.macgurus.com) for the difference in cost.
- capacity -
Firewire enables larger capacities.
the largest single scsi drive listed (pricewatch.com) is 180gig.
the largest IDE listed drive is 320gig, and as this thread started
discussing, a 400gig drive is ready for market.
- RAID -
when looking at (hardware) RAID enclosures recently, in every instance I
recall, scsi RAID enclosures were either the same, or more expensive
than firewire enclosures of the same bay count, and RAID level
supported. Again, given a fixed number of drive slots 2, 4, 5, 8
whatever, for less $ you can get greater capacity, and the same RAID
level, using firewire rather than scsi.
- availability -
scsi, is NOT built-in on any new Mac, and has not been standard since
the introduction of the iMac in 98. scsi, as far as I am aware, is NOT
standard on any major brand PC. In other words - having scsi on a new
computer is an additional cost, and *might* cause additional
instabilities depending on the scsi card, drivers, and other
hardware/software specifics.
Firewire is included on EVERY new Mac, and has been included on every
Mac since the introduction of the eMac (2001?), and has been included in
every Mac tower since the introduction of the B/W G3 tower (which was I
think 98).
Firewire is also included on some, I do not know a percentage, new PCs.
I know most, if not all, Sony PCs come with firewire (they call it iLink
but it is firewire). And it has been available since at least 99.
Firewire comes on *EVERY* DV camera, and a few still digital cameras.
I understand, that some stereo equipment manufacturers are also
including firewire. Scsi comes on NONE of these.
So....
your reasons for using scsi - other than legacy - are??
