Hard Drive Info 2

There are roughly two categories that harddisk manufacturers design their products for. The first category is the general purpose PC that’ll be used in offices and at home. The criteria for harddisks used in these PCs usually are low noise and heat production. Simply because they’ll feature in PCs that are used throughout the day for all sorts of office applications. A good example is an office PC, where somebody will be working at throughout the day; low noise is an important factor there. Low noise and heat production are usually more important than raw performance as normal office applications aren’t that taxing on a PC’s harddisk anyway. In these kinds of PCs we’ll often find 5400-rpm harddisks with a storage capacity ranging from 20 to 80Gb. In this test we’ll therefore look at the following 5400-rpm harddisks with a capacity of either 40 or 80Gb:

Harddisks 5400-rpm, 40 and 80GB:
 
Seagate ST340810A - 5400-rpm - 40GB
Maxtor D540X 4D- 5400-rpm- 40GB
Samsung SV4012H - 5400-rpm - 40GB
Western Digital WD400AB- 5400-rpm- 40GB
Seagate ST380020A - 5400-rpm - 80GB
Maxtor D540X 4D- 5400-rpm- 80GB
Samsung SV8004H - 5400-rpm - 80GB
Western Digital WD800AB- 5400-rpm- 80GB


The second category is the performance PC, which normally uses harddisks with 7200-rpm spindle speeds. These harddisks are naturally perfectly capable of functioning in a general purpose or office PC too but are generally too costly, or a bit overkill, for mundane office applications such as word processing or sending emails. Only when the office or home PC is used for heavier applications such as 3D modeling, CAD/CAM or hosts a large database of clients we’ll start to see the benefits of using a 7200-rpm harddisk. With these harddisks low noise and heat production are still important criteria but performance is generally more important. From our tests we’ve seen there’s a whole range of different approaches to manufacturing 7200-rpm harddisks, some manufacturers aspire to produce the absolute fastest harddisk whereas others focus on producing the most silent 7200-rpm harddisk. In our roundup we’ve looked at the following 7200-rpm disks ranging in capacity from 80- to 120Gb.

Harddisk 7200-rpm, 80 and 120GB:
 

Seagate ST380021A - 7200-rpm - 80GB
Maxtor D740X- 7200-rpm- 80GB
Samsung SP8004H - 7200-rpm - 80GB
Western Digital WD800BB- 7200-rpm- 80GB
Western Digital WD800JB - 7200-rpm - 80GB
IBM 120GXP- 7200-rpm- 80GB
Western Digital WD1200BB - 7200-rpm - 120GB
Western Digital WD1200JB- 7200-rpm- 120GB
IBM 120GXP - 7200-rpm - 120GB

 

We’ve made considerable effort to make sure we took accurate measurements of the noise and heat production levels of the harddisks tested. For the noise production, or rather sound pressure level, measurements we’ve used a professional sound pressure level meter costing several thousands of dollars and calibrated according to IEC-60651, Class-1. The actual measurements are in dB with an A-weighted curve to fit the sensitivity of the human ear, the maximum error is +/- 0.7dB. All of the given values are therefore in dB(A). All of the harddisks tested were mounted in a soundproof and fully insulated enclosure so as to make sure we measured the sound level generated by the harddisk and not the ambient noise. The microphone in all of these tests was at a distance of 25-cm or 10-inch from the top surface of the harddisk.

Because the measurements are in decibel (dB) we do need to take into account that decibels are measured on a logarithmic scale. So it is important to note that a sound pressure level of 30-dB isn’t 10-times higher than 20-dB but 100-times. For example, if comparing a sound level of 60-dB, a normal conversation, to 90-dB, an average lawn-mower, there’s a 1000-times difference in sound pressure level. So decibels are a lot harder to quantify because a doubling in sound pressure level isn’t simply a doubling of the dB value.

Sound Pressure Levels:
 
0-dB - threshold of hearing, total silence
15-dB - whispering, leaves rustling
30-dB - very soft music, dishwasher
60-dB - normal conversation, vacuum cleaner
90-dB - lawn-mower, motorcycle
120-dB - threshold of pain, jet-engine
150-dB - hearing damage, heavy fireworks


The temperature measurements are done with a professional, laboratory grade, digital thermometer calibrated in degrees Celsius with a maximum error of +/- 0.1 degree. All the measurements are done in the open air with a constant room temperature of 21 C/ 70 F. De actual measurement is to the upper side of the drive with the probe attached to the metal top with a clamp at a set pressure. The drive was used for an hour prior to the measurement and the average temperature over a period of 15-minutes was used as the result. The result reflects how many degrees the harddisk is warmer than room temperature, as this will help you to determine what the harddisk’s temperature will be when mounted in a system with a certain temperature. If you however are interested in the actual disk temperature under the conditions we tested just add 21 degrees Celsius.

Test system configuration:
Asus P4T-E motherboard, i850 chipset
2 x 256MB Samsung PC-800 RDRAM
ATI Radeon 8500 64MB
Toshiba SD-M1612 DVD/CDROM
Windows XP Pro with latest updates

 

If we look at the HDtach results one thing is obvious, the 5400-rpm harddisks are no match for any of the 7200-rpm harddisks. The difference between the fastest and slowest disk in this roundup is a massive 64% (40618/24755). If we however look at the scores for 5400 and 7200-rpm averaged, the 7200-rpm harddisks are on average 31% (38513/29339) faster. A clear-cut conclusion you might think, 7200-rpm harddisks are faster, period. Unfortunately we couldn’t be further from the truth. HDtach is a sequential benchmark and as such is useless if you’re looking for real-world results. It simply measures the maximum throughput in Kb/s across the platters, working from the outside in. In a real-world situation the harddisk will never read or write data from/to the platters sequentially but rather scatter the data all over the platters. Nevertheless HDtach gives a good indication of what the harddisk is capable of; a good reference to compare to the real-world benchmarks.



 Hard Drive Info 3