Philipp Thomas wrote:
* Paul Abrahams [Sun, 06 May 2001 10:20:38 -0400]:
My hard drive claims to be ATA100; the motherboard claims UDMA 33/66 IDE. I'll admit that I know nothing of the relationship between ATA and UDMA, but I had assumed that the numbers were comparable, especially since most hard drives seem to be ATA66. Can you enlighten me?
Yes, they're used interchangeably. BTW, what hard drive is it exactly? But just try to run 'hdparm -tT /dev/<your disk>' (and please post the output :). If you get Numbers below 66 MB/sec (and *no* currently available hard disk even comes near that), it won't get any faster when connected to a ATA100 controller.
Well, there are two numbers, one above 66MB/sec and one below: root@suillus:/aux/home/pwa > hdparm -tT /dev/hda /dev/hda: Timing buffer-cache reads: 128 MB in 1.10 seconds =116.36 MB/sec Timing buffered disk reads: 64 MB in 2.03 seconds = 31.53 MB/sec I'll see what happens when I attach the controller.
So if you've bought the controller for higher speed, you've wasted your money. But at least you've now got two more ATA channels, so you can run four ATA devices as master on their own channel. Running ATA devices as master on their own channel is always the best way to attach them as that will give you the most speed when talking to them in parallel (like installing from CD) and will avoid trouble.
That's good to know. Paul