I agree with Jay. That said, I have used many external USB drives at 5400rpm with absolutely no problems. Better to be safe though whenever possible.

Mike

I bought an HP with two drive bays (I think that many of them come that way). There was a single 5400 rpm drive in one bay and I put a 7200 rpm drive in the second.

Also, many laptops come with eSATA ports. An external eSATA drive is as fast as an internal drive and blows the Mac Firewire 800 out of the water. My laptop has an eSATA port that I use for video editing in my studio.

Faster is always better, right? Not always cheaper, though. I have used 5400 laptop drives and for small jobs they work fine. I have had performance issues when trying to access several video files at the same time, like a multicam project.

If money is no object, go with the eSATA route as described above. If you are on a budget, consider the types of projects you need to do and adjust accordingly.

The recommendation to use 7200RPM drives comes from the days of tape capture where the tape deck is sending frames at a fixed rate and your hard drive had better be fast enough to store them in real-time. If you are not using tape based camera then the need for 7200RPM drives disappears (i.e., becomes a "nice-to-have" not a "necessity"). You may reach a limit with a multi-cam project though. Chances are that a tape-less camera is using a highly compressed video format that will overwhelm your weak laptop CPU and hard drive through-put will be the least of your problems. ;-)

I have never had a laptop with anything faster than a 5400RPM drive and I have always edited video on them. It's not the fastest experience but it works in a pinch. I do all of my serious editing on a desktop. If the laptop was my only workstation, I would probably get a 7200RPM drive for productivity sake.

~jr

I agree with JR. 5400 rpm drives have a fast enough throughput to handle editing most compressed formats. More often than not the CPU (and to a lesser extent RAM) are the limiting factors.

If I was consistently editing full AVCHD, it would be an interesting side-by-side test to see if the faster drive alone offered an advantage with timeline responsiveness. My first guess is that it wouldn't make much of a difference.

While 7200 rpm drives are certainly preferable, today's 5400 rpm drives are plenty speedy in the sustained transfer rate department. The amount of data they can cram on a single drive platter has increased dramatically due to advances like perpendicular recording. The amount of data flying under the head as the drive spins is considerably higher than it was just a few years ago. It's called "areal density" and is measured in bits per square inch. In 2005, consumer hard drives were between 100 and 150 Gbit/in². In 2005 Toshiba introduced a new hard drive using perpendicular recording, which achieved a density of 179 Gbit/in². Recently Seagate Technology has demonstrated a drive with a 421 Gbit/in² density. It is expected that perpendicular recording technology can achieve a maximum density of 1 Tbit/in². This ever increasing areal density makes for ever increasing sustained transfer rates without increasing how fast the platter spins.

Keep in mind that DV, HDV and AVCHD compressed video only take a real-time transfer rate of around 4 megabytes per second. The minimum transfer rate of a modern drive is at least 10-25 times that fast. If you have multiple tracks of video going in Vegas, the drive's access time (basically the time it takes for the drive's head to go from one part of the disc to another and start reading data) is going to be far more important. If you have the option (and the cash), get a 7200 rpm drive, but a modern 5400 rpm drive will usually be more than adequate.

(Seagate's ST9640320AS is a 2.5" 640GB 5400 rpm SATA-II drive which sells for about $75. It has an average read speed coming in at 72.72MB/sec.)

I just bought a Seagate Go Flex Desk 2TB external USB 2.0 drive, and hooked it to my Q6600 running Win 7 64 and Vegas 10,0a 64. I started a render (AVCHD 1440 x 1080 source on an internal HDD) to the Seagate instead of another of my HDDs, and found the CPU was still pegged at 100%.

Interestingly, I cannot find anywhere that Seagate reveals this drives RPM speed...my guess from the little noise and vibration, is that it is running 5400 RPM.

So it seems I can render to an external USB drive without taking a speed hit.

What results would be with an i7 chip I cannot guess.

Fred

Marks,

Be sure the drive is at least 5400. i have an HP that is several years old, that has a 4000 rpm drive. I've captured DV25 with no problem, but it is noticably sluggish

"In 2005 Toshiba introduced a new hard drive using perpendicular recording.."

Actually, it was Hitachi. IBM had been working on it when they sold their hard-disk division to Hitachi in 2004.

As john said - it's the sustained data rate that matters. Not the platter speed. (Heck, the fastest HDD is zero RPM).

While IBM (Hitachi) has been responsible for most of the significant advances in hard drive technology, it was in 2005 that Toshiba introduced the first commercially available drives using perpendicular recording. Here is a Toshiba press release from December 2004.

http://www.toshiba.co.jp/about/press/2004_12/pr1401.htm

Seagate began shipping perpendicular recording drives in January of 2006.

Hitachi did not release a drive using the technology until mid-2006.

I did speed tests (100MB, sustained, no cache) on various drives including 5400's via USB2, getting around 180Mb/s. In theory, more than enough for compressed formats like DV/HDV (25Mb/s) or XDCAM-EX (35Mb/s) or their equivalents in "visually lossless" formats. Depends how many channels.

The speed test utility I used was QuickBench in the SpeedTools suite, which is available for both Win and Mac.

I think the speed is USB2-dominated, as I have found similar figures for 7200 USB2 drives in the past. Not sure why it is that low though - USB2 reportedly has a sustained rate of 300Mb/s (480 being non-sustainable).