BARE FEATS - real world Mac speed tests

What Happens When The Newest, Fastest Ultra ATA Drives Are Put In A FireWire Enclosure?

October 18th, 2001
rob ART morgan, Bare Feats Mad Scientist

I took the THREE FASTEST ULTRA ATA/100 drives tested recently and stuck them in a Granite Digital "Oxford 911" FireWire enclosure to see how fast they would go. Like me, many of you like the fact that you can jerk a drive out of your G4 Tower and shove it into a FireWire case.

But then, will it go faster in a FireWire case? slower? I got bit of a shock with the Apple 'generic' FireWire enablers. Take a look at this graph:

Using the Apple 'generic' FireWire extensions, the speed of of the Barracuda dropped from from 41MB/sec to 23MB/sec! But then I reformatted it using FWB's HD Toolkit 4.5 and used FWB's FireWire extensions (Library and Governor), the speed went back up to 29MB/sec. I wondered if FWB knows something that Apple (and all the other driver makers) don't know because all three new test drives ran faster under FireWire when FWB drivers were used.

FWB didn't reveal any secrets but did remark that these new drives are a challenge for FireWire case and driver makers because they exceed the usable bandwidth of a Mac FireWire system (and probably any other). This means that the FireWire bus will not be able to empty the buffer on the drive as fast as the media fills it. It's like having a Ferrari engine that revs to 10,000 rpm and installing a rev limiter that forces it to misfire at 5000 rpm.

At any rate, the graphs below show how fast the fastest Ultra ATA drives go when put in a Granite Digital FireWire case and run with the FWB drivers.

(The WHITE bars indicate three FireWire units that come prepackaged with drives as a reference.)








The IBM 60gxp seems to be the "happiest" of the three fastest Ultra ATA drives in a FireWire case. The Maxtor D740X was the second fastest. The Seagate Barracuda ATA IV came in third place even though it came in first place when used as a pure Ultra ATA drive inside the G4 tower. Goes to show you that you can't assume a fast Ultra ATA drive will be equally fast in a FireWire case.

Thanks to FWB HDToolkit, these three fast Ultra ATA drives performed as well as the best "prepackaged" FireWire drive units. Unfortunately, no drive runs as fast in a FireWire case as it does inside the G4 tower using the Ultra ATA interface. (See my soliloquy below.)

Note the very good Quicktime Playback speed of the Maxtor 3000DV. It's obviously optimized for DV playback. Maybe that's why they call it "DV."

If you have a G4 tower and want extra storage and the fastest transfer speeds, I suggest you install extra drives inside the tower (which holds up to 4) and get either the new Tempo ATA100 PCI controller card from Sonnet or the new 6880M True Hardware RAID ATA-133 PCI controller card from Acard. (Read my REPORT on these two Ultra ATA controller cards.)

If you are like me and often move a drive back and forth between the inside of the tower and a FireWire enclosure, you'll want a drive that doesn't take a large performance hit when running in FireWire mode. In that scenario, the IBM 60gxp earns the "fastest drive on both interfaces" award.



People are often dazzled with the theoretical "400 megabits per second" rating of FireWire and think that if they put an Ultra ATA/100 drive in a FireWire case, it will go "wicked fast." Not so. The 400 megabits translates to 50 megabytes per second (MB/sec). The ATA/66 internal interface of the G4 tower is capable of 66MB/sec. The Tempo ATA100 PCI controller from Sonnet is capable of 100MB/sec. So Ultra ATA still has the edge over FireWire.

Also, since there isn't such a thing as a true FireWire drive, the Ultra ATA drives are used in conjunction with a FireWire-to-ATA bridge board to create the FireWire storage unit. You can be sure that something's lost in the translation. Some of the bridge boards don't even use 80 conductor cables. FireWire engineers indicate to me that the usable bandwidth of a FireWire enclosure/bridge board is a good amount less than 50MB/sec.

Even if Apple releases 800 Mbits/sec FireWire, the drives still won't go any faster. Even if faster FireWire bridge boards are invented, the ultimate bottleneck is the drives themselves. The fastest drive in the group has a maximum sustained transfer rate of 41MB/sec. That doesn't come close to the 50MB/sec theoretical rate of FireWire or the 66MB/sec theoretical rate of ATA/66.

Until faster drives and FireWire subsystems are invented, the only way to make FireWire storage go faster is to create striped arrays using RAID software... but that's another story. STAY TUNED!



The test "mule" was an Apple Power Mac G4/800MP running OS 9.2 with disk cache set to 512K (to diminish effect of system caching), AppleTalk OFF, Virtual Memory OFF, and Extensions set to minimal (BASE).


Seagate Barracuda ATA IV (ST380021A) 80GB 7200rpm ATA/100

Maxtor DiamondMax Plus D740X (6L080L4) 80GB 7200rpm ATA/100/133
(note model number ending in "L4" has fluid dynamic bearing motors)

IBM Deskstar 60gxp 60GB 7200rpm ATA/100


Granite Digital FIREVue™ FireWire 1394 / Ultra IDE CASE KIT


EZQuest Cobra 60GB 7200rpm

Maxtor 3000DV 60GB 7200 rpm

VST/SmartDisk full height 45GB


WHERE TO BUY (last time I checked) had the IBM and Seagate drives in stock. They had the Maxtor D740X model but not with fluid dynamic bearings. If you want the fluid bearings, you'll want model #6L080L4, not model #6L080J4. (No reseller seems to have it yet.)

Another good source for drives is Other World Computing. They carry a full line of Macintosh products including their own line of FireWire enclosures (with and without drives).

Looking for a FireWire case? The case I used in the test was the one from It was the fastest of the "driveless" FireWire enclosures I've tested. It's the only case I've tested that uses 80 conductor cable between the bridge board and the drive. It can be a bit noisy as it has two fans (one for the power supply and one for the drive).

It's a bit of an ugly duckling in a time where sleek cases are the rage. I like the clear Elite "911" case that Other World Computing is selling. FWDepot sells a nice looking thin "driveless" case that includes a fan. It's called the "TT3.5" and does have the Oxford 911 chip set.

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© 1995-2007 Rob Art Morgan
"BARE facts on Macintosh speed FEATS"
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