Firewire and USB2 are two welcome replacements for external scsi. With hot plugging, no id conflicts, and no terminators, the headaches of having a fast external drive are now gone. Most computers now come with both Firewire and USB2 built in, meaning the only decision to be made about choosing one comes when buying periherials. With USB2 having a theoretical bandwith of 480Mbit/sec, it is expected to be a bit faster than 400Mbit/sec Firewire. But specs do not always tell the whole story, so here are some benchmarks.
Test Setup
To conduct these tests I used a Western Digital 120 gigabyte hard drive inside a Bytecc ME-320U2F external drive enclosure. This enclosure can accept IDE hard drives up to 300 gigabytes, and connect to a computer using either USB2 or Firewire. The enclosure accomplishes this by using a Oxford 911 chip for Firewire, and an Ali chip for the USB2.
I performed USB2 and Firewire tests on two computers. A desktop computer using an NForce2 motherboard with a PCI Firewire card, and a Centrino laptop with both USB2 and Firewire built in. The IDE test was performed on the Desktop machine, and is for reference.
Test Configuration
External Enclosure:
Bytecc ME-320U2F
Firewire chip: Oxford 911
USB2 chip: Ali
Western Digial 120 Gigabyte 8 Megabyte Cache Hard Drive
Laptop:
IBM Thinkpad X31
Windows XP Professional SP1
Firewire chip: Ricoh R5C552
USB2 chip: Intel 82801DB/DBM
Desktop:
Epox 8RDA NForce2 Motherboard
Windows XP Professional SP1
Firewire chip: Texas Instruments TSB12LV26
USB2 chip: NForce2
Tests
All tests were performed using HDTach 2.6
| RESULTS |
| BUS | Average Read (KBps) | Average Write (KBps) | CPU utilization (%) |
Conclusion
From these results we see that Firewire trounced USB2 in two ways. The first was that data was read almost twice as fast as USB2. Writing data occurred at similar speeds using both Firewire and USB2. The second advantage appeared from the CPU utilization. On both computers, Firewire used a significantly less amount of the CPU than USB2 when transferring data. According to these benchmarks, Firewire appears to be the better choice for an external hard drive.