How fast is fast enough?

3 replies [Last post]
Richard
Offline
Joined: Jul 19 1999

I am looking to buy an extra hard disk to supplement my existing IBM 10.1Gb. There seems to be a lot of hype surrounding 7,200rpm disks (Matrox and IBM sites) with claims of these drives giving greater performance increases than a +100MHz chip.

This may be true but there is a price premium and with the Maxtor 17.2Gb 5,400rpm drive on sale in Dabs Online for £125+VAT, I am struggling to justify the faster drives.

Does anyone know if the Maxtor is fast enough to handle DV - real world as opposed to what the specs. say? I use Hi-8 at present, 7:1 compression, but I would like to 'future proof' a little.

PC: PII350, Marvel, 128Mb, 10.1Gb, Win98. Purchased July 98.

Unicorn
Offline
Joined: Apr 12 1999

Your system is almost identical to mine (video hardware aside), except that I already have the Maxtor drive as well as the 10GB IBM drive. My experience is that the IBM drive isn't quite fast enough to reliably capture DV on the slow end of the disk, but the Maxtor works fine; the IBM drive loses maybe one frame in five hundred in DV captures when the disk is almost full, the Maxtor has never lost a frame.

P4-3.06/2GB RAM/2500GB IDE/SATA. Avid Media Composer, Liquid Edition, Premiere 6, Lightwave, Vue 6, eyeon Fusion 5. DV and HDV editing/compositing.

RichardJ
Offline
Joined: May 7 1999

A drive isn't necessarily faster just because it is 7200 RPM. The continuing increase in drive capacity is being achieved because the makers can cram the bits on the medium surface closer and closer together. The closer they are, the more bits/sec pass under the heads, thus increased capacity generally means increased speed.

All other things being equal, a 7200 RPM drive might be faster, but there are so many factors involved it doesn't always apply. The most important parameter of a disk drive as far as performance is concerned is it's sustained throughput. Unfortunately this is hardly ever mentioned in a drive's specs - you get seek time, interface speed, RPM, buffer size, maybe even no. platters, but the really important number is difficult to find.

My feeling is that all modern drives are likely fast enough, probably exceeding 10 MB/sec throughput. I will say a point in Maxtor's favour though, which is that their drives always seem to maintain good throughput even on the inner tracks. Many drives tail off badly as the heads get towards the centre, but Maxtor's always seem to hold up well. This is very important for video if you want consistent results.

------------------
Richard Jones

Richard Jones, http://www.activeservice.co.uk
Home of the MediaStudio Pro Tutorial - Edition 3 for MSP 7

Richard
Offline
Joined: Jul 19 1999

Unicorn, RichardJ,
Thanks for your replies. I'm going to give it a couple of months and see if the IBM 25Gb 5,400 drive drops significantly in price - if not, Maxtor, here I come :)