PERFORMANCE
                     ANALYSIS
                     
                     There's
                     no significant difference in the speed of these
                     two FireWire drive enclosures when using them
                     with the same drive on the same
                     machine!
                     
                     However,
                     as you can see from the graphs above, not all
                     Macintoshes are created equal when it comes to
                     FireWire interface speed. 
                     
                     In
                     my previous report on 2.5 inch FireWire drives,
                     I observed the "slowing" of FireWire transfer
                     speed when moving from a Desktop to a PowerBook.
                     All PowerBooks
                     (including the Titanium) max out at 16MB/sec
                     sustained write no matter what FireWire drive
                     you use. So? So you'll be dropping frames
                     according to digital video editors. Look at this
                     summary graph and let it sink in:
                     
                      
                     
                      
                     
                     In
                     this test session, I was blown away by the
                     difference between the write speed of the Dual
                     G4/533 and the Sawtooth G4/500. I don't know if
                     it's a different FireWire controller chip or
                     firmware or what. (It's not the OS or FireWire
                     software since all three Macs used the same
                     versions.) And does the speed increase observed
                     on the Dual G4/533 carry over to all newest
                     models of G4 (466, 667, 733)? I'll report back
                     in a few days.
                     
                     The
                     graphs at the top of this report reflect the
                     speeds measured using a 30GB IBM 75GXP 7200rpm
                     in both enclosures. I tried two other fast
                     ATA/100 7200rpm drives with very similar
                     results. (40GB IBM 60GXP and 20GB Fujitsu
                     MPG3204AH-EF) The chart below shows the relative
                     speed of the drives when used in the Granite
                     Digital enclosure and connected to the Dual
                     G4/533.
                     
                      
                     
                     
                     
                     
                     
                       
                     
                      
                     
                     Caution: Not all drives
                     from the same manufacturer yield the same
                     performance. Recently I received four
                     Fujitsu drives -- all identical models,
                     identical capacity, identical manufacturing
                     date, and identical factory. Yet two of them did
                     sustained READS at 39MB/sec and two at 19MB/sec.
                     I also received two IBM 60GXP drives --
                     identical capacity, identical manufacturing
                     date, identical factory. One does sustained
                     WRITES at 33MB/sec. The other writes at 3MB/sec.
                     (No, that's not a typo.) Needless to say, the
                     slow drives are being sent back.
                     
                     I have three suggestions that
                     will protect you from sub-performing drives:
                     1. Test the drive when you get it.
                     ExpressPro-Tools is free (see the bottom of this
                     page).
                     2. Contact the manufacturer or visit their web
                     site. Maxtor posted a tech bulletin on their
                     80GB ATA/100 drive indicating that the drive
                     does a rigorous write verify the first 10 times
                     the drive is powered up. After than, the drive
                     writes much faster.
                     3. Buy from a reputable dealer who will exchange
                     drives or refund your money if you are not
                     satisfied with the performance.
                     
                     
                       
                     
                     Miscellaneous
                     Observations
                     
                     The
                     Granite Digital uses an 80 conductor ribbon
                     cable to connect the bridge board to the drive.
                     The Mercury Elite uses a 40 conductor cable.
                     Hmmm.
                     
                     The
                     Granite Digital has a cooling fan and the OWC
                     Mercury Elite does not. That means the OWC unit
                     is runs quieter but warmer.
                     
                     The
                     Granite Digital enclosure is 9.75 X. 6.5 by 2.5
                     inches while the OWC Mercury Elite is 8.5 X.
                     5.25 X. 1.5 inches (not counting external power
                     transformer).
                     
                     The
                     Granite Digital enclosure weighs 4 lbs 3 oz
                     including drive and power cable. The OWC Mercury
                     Elite weighs 3 lbs 5.5 oz including drive and
                     power transformer.
                     
                      
                     
                     WHERE
                     TO BUY?
                     
                     Other
                     World Computing
                     sells the Elite version of their Mercury
                     FireWire enclosure without a drive for $139. You
                     can also buy it with a 40G
                     IBM 60GXP
                     for $310. 
                     
                     Granite
                     Digital
                     sells their enclosures
                     for $159. They also have drives and
                     PCI
                     controllers.
                     In fact, if you build your own FireWire
                     enclosures, they will sell you the bare
                     FireWire/IDE
                     bridge board.
                     
                     
                     FLASH! FWDepot
                     is now selling an enclosure with the 911 chip
                     set which is very similar to the one sold by
                     OWC. It goes for $140.
                     
                     The
                     primary test drive was an IBM 75GXP 30G ATA/100
                     7200rpm drive courtesy of Trans
                     International
                     who sells them for $149. 
                     
                     The
                     IBM 60GXP 40G ATA/100 7200rpm drive was provided
                     courtesy of Other
                     World Computing
                     who sells them for $200 without the FireWire
                     case, $310 with.
                     
                     The
                     Fujitsu 20G MPG320AH-EF ATA/100 7200rpm was on
                     loan from Fujitsu. I haven't found a good source
                     yet.
                     
                     Don't
                     have FireWire in your G3 PowerBook?
                     FWDepot
                     has a good CardBus card with two ports for $86.
                     Don't have FireWire on your Desktop? Get a PCI
                     controller. The fastest PCI FireWire/USB combo
                     card I've tested was the USB/FireWire PCI card
                     from FWDepot.
                     If you don't need USB and just want to add more
                     FireWire channels, then you might hold out for
                     the soon to be released Granite
                     Digital 3 Channel PCI
                     controller.
                     
                     
                     See
                     the STORAGE section of my HOT
                     DEALS
                     page for other sources for these
                     products.
                     
                      
                     
                     TEST
                     NOTES
                     
                     SUSTAINED
                     READ AND WRITE
                     The sustained read/write benchmark was run using
                     ExpressPro-Tools
                     2.5
                     (SCSI and Fibre Channel version 2.5 for Mac).
                     When you launch it, it displays all the mounted
                     drives (IDE, SCSI, FireWire). Select the drive
                     you want to test (one click). Then go to the
                     Utilities menu and select Benchmark Volume. A
                     test window will appear. Set Max Transfer Size
                     to 8MB. Then press start. On my graphs I display
                     sustained rate, not peak rate. Peak rate is
                     skewed by the drive cache and doesn't reflect
                     real world performance.
                     
                     RANDOM
                     READ AND WRITE
                     I use Intech's QuickBench utility to measure the
                     random read/write speed at various size transfer
                     "chunks." The graph shows the random transfer
                     speed using 1024K block size.