WD Scorpio Black

I’ve seen and read plenty of these guides on the Internet, but I have yet to come across an article that my mother would understand. Don’t get me wrong, my mom is no geek, in fact she’s quite the opposite. She’s the type of mom that struggles to open an email… but I digress. I figure if you’re looking for any kind of guide on the Internet, you want it to be concise and to the point, and that’s what I intend to do.

So, what do you need to look out for when you’re looking for a new hard drive for your laptop?

Rotation Speed

Arguably the single most important factor in a hard drives performance, the spindle speed. Simply put, this is the speed at which the hard drive platters rotate. Roughly speaking, the faster the better. These days, most mid laptop drives are 5,400 RPM devices, however, with ever more competition in the field of mobile performance, we’re now beginning to see 7,200 and even 10,K RPM drives for laptops. Generally speaking, a 5,400 drive is absolutely fine for regular users, but if you’re a power user, you might want to look into a 7,200 drive.

The latest drive from Western Digital, pictured here, are as close as it gets to high performance before you step onto the realm extreme performance. You can get your hands on a 10,000 RPM 1.8″ laptop drive, but in my opinion, the added noise isn’t worth the hassle.


The longer you spending looking for something, the longer you’re going to take to find it. At least that the general rule. That same principle can be applied to this particular hard drive specification. Seek time is the time a drive head takes to read the appropriate location on a disk. As a rule of thumb, the shorter the seek time, the better. In the current market, average latency numbers around 5-6 ms and seek times below 2.5 ms make for a good performance drive.


The buffer on any hard drive acts as a half-way house for data read from the disk and passed on to the CPU, memory etc… In terms of performance, larger buffers allow transfer of more data in the same amount of time, meaning less of a bottle neck for your system. Most hard drives for mobile computing come saddled with 8MB of buffer space, but if you’re looking for some high grade hardware, you’re likely to come across some devices with a 16MB buffer.

Form Factor

Generally speaking, laptop hard drives come in 1.8″ variants. This size refers to the diameter of the hard drive’s platter. Though the most important numbers you need to pay attention to are the dimensions of the case itself. More often than not, you’ll find that a most drives are H: 0.374 Inches L:3.94 Inches and W: 2.75 inches. Check with your laptop manufacturer before purchasing a new drive.

Drop Detection

This is a relatively uncommon feature, mostly found in high end hard drives. Essentially, if you’re unfortunate enough to drop your laptop, the hardware will automatically park the reading head, almost instantly. Why is this good for you? Well, it helps to prevent irreparable scratch damage to the platters. If you’re the clumsy type, this might be a worth while feature. Double check the spec sheet on this though, as manufacturers often give their products very similar IDs but differing features.

Operating Volume

Noise levels are more down to personal preference rather than performance. For me, I’m not put off by a slightly louder drive, if the performance benefit is there. Granted, most 7,200 RPM drives will naturally produce louder idle and busy sound, but it’s a worth while pay off for the benefits. If on the other hand you hate the sound of anything but silence, then a quitter 5,400 RPM drive might be for you. If you think that 22dB is similar to a quietly spinning laptop fan, this should give you a better idea of actual noise levels.

Power Consumption

Depending on the manufacturer, the hard drive you choose might have a significant effect on the power cycle of your battery. In most cases, you’re not going to see a major difference, but if you decide to go for a major upgrade in specs and performance, you might find that you battery cries wolf more often that usual. Be sure to read the power consumption stats carefully and compare them to your current device.

Hopefully by now you have  a solid understanding of the fundamentals of hard drive technology. I’ve tried to keep this guide as high level as possible to keep from falling into the trap of alienating readers, but if you’d like more detail about choosing the right hard drive for you, perhaps this might help.