Now There Are At Least Two FireWire Drive Enclosures Using The "Oxford 911" Chip Set. Which one is fastest?

April 24th, 2001
rob ART morgan, Bare Feats Mad Scientist

Up until April 2001, Granite Digital was the ONLY FireWire enclosure/bridge board maker to ship with the new FAST Oxford 911 chip set. Now Other World Computing is shipping the Mercury Elite which boasts the same chip set. "Is it just as fast as the Granite enclosure?" Let's find out.

Both new FireWire drives were tested on three different Macs:
Dual G4/533 MiniTower, G4/500 "Sawtooth" MiniTower, and the Titanium G4/500 PowerBook.





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.



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.



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.

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.



LINKS to SPEED tests on other web sites


DOWNLOADS that add more SPEED





© 2001 Rob Art Morgan.
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