LVD shootout

The Tests

Test System Configuration
Processor	Celeron 366 on MSI-6905 riser card
RAM	128MB PC100 Hyundai SDRAM
Motherboard	Intel BX Chipset with Slot-1
Hard Drive	Quantum Atlas IV 18.2GB Western Digital Enterprise 18.3GB
Operating System	Windows 98 Second Edition Build 4.10.2222A
Software Used	Disk WinMark 99 and High-End WinMark 99
Other Hardware Used	Adaptec AHA-2940U2W PCI SCSI card

The tests we ran were based on the WinBench Disk WinMarks and the High-End Disk WinMark.

Disk WinMark Results
Disk Make and Model	Quantum Atlas IV	Western Digital WDE18310
Business WinMark (kBytes/s)	4140	4220
High-end WinMark (kBytes/s)	14200	14800
Disk Access Time (milliseconds)	11.5	8.95
Disk CPU Utilization (Percent Used)	3.4	5.54
Disk Transfer Rate : Begin (kBytes/s)	21600	27800
Disk Transfer Rate : End (kBytes/s)	13700	18200
Disk Playback High-End Overall (kBytes/s)	14200	14800
Disk Playback High-End Photoshop 4.0 (kBytes/s)	8490	9700
Disk Playback High-End Premiere 4.2 (kBytes/s)	15100	15900
Disk Playback High-End Visual C++ 5.0 (kBytes/s)	15500	15800

As you can see from the results of the test, the Western Digital comes out the obvious winner of the two although not by much. Most of the performance difference is due to the hard disk electronics, the way the disk recording electronics work as well as the algorithms used in the disk software. Although both disks spin at different rotational speeds, they probably have more or less the same mechanism architecture. The most important number to look for when purchasing the LVD drives is the sustained data transfer rate, this will ensure that the data transfer rate desired is maintained. This will also tell us the linearity of the transfer rate. Although both drives are about the same capacity of 18.3GB each, the gain in performance from using a 10,000 RPM rotational speed is not much.

The Adaptec SCSI card also plays an important role in the overall performance of any hard disk sub-system. Adaptec is also well known as the leader in SCSI technology and is the defacto standard when it comes to SCSI cards and chipsets for SCSI devices in the mainstream PC industry. The card that we use is the one recommended for such application and is the best one that I have used so far. There are alternatives if the Adaptec costs too much but I will not cover that here now.

Conclusion

The performance and speed of LVD drives are ideal for those high-bandwidth applications like video and photo editing. After all they are designed for this type of application. This performance comes at a pretty high price. If you have the need for speed and the high cost doesn't deter you, the U2W LVD hard disk drives are for you. Until anything else faster comes along this system is your best bet.

Although FireWire offers higher performance and speed than SCSI U2W LVD, it is still pretty much niche and has yet to take-off. The cost and availability is still not as easily reached as what SCSI offers. Besides the PC industry hasn't adopted it as the high-speed standard in servers and workstations in a big way yet. For now, SCSI is still the way to go for cheaper and faster disk performance.

Hard Disk Specifications
Model		Quantum Atlas IV 18.2GB	WD Enterprise WDE18300
Interface		Ultra2/Ultra SCSI 68-pin
Formatted Capacity		18,200 MB	18,310 MB
Number of Disks		4	4
Number of Heads		8	8
Bytes per Sector (STD)		512	512
Average Read Seek		6.9 ms	5.2 ms
Average Write Seek		-	6.2 ms
Track-to-Track Seek (Read)		0.8 ms	0.6 ms
Track-to-Track Seek (Write)		0.8 ms	0.6 ms
Full Stroke Read Seek		15 ms	13 ms
Full Stroke Write Seek		15 ms	14 ms
Average Latency		4.17 ms	2.99 ms (nominal)
Rotational Speed		7,200 RPM	10,036 RPM
Data Transfer Rate	Media to Buffer	-	45 MB/s max
	Buffer to Host	80 MB/s max
Buffer Size		2 MB
Average Power Requirements		-	14.14 W
Weight		0.64 kg	0.73 kg