Subject: Re: UDMA downgrading
To: None <>
From: Thomas Hertz <>
List: current-users
Date: 10/15/2003 21:16:53
I really hadn't read that part of the ATA specs (and none of the other 
parts I must admit *ahem*), but it didn't help putting the disks in the 
end of the cables either. =(
The cables are the ones that came with the Promise cards, and they seem 
to be of good quality. I don't think that my server chassi is any 
"noisier" than any other chassi, so it seems like I'm stuck here.

Thomas Hertz

Charles M. Hannum wrote:

>On Wednesday 15 October 2003 06:14 pm, Thomas Hertz wrote:
>>What is the problem here? I've gotten all kinds of suggestions from a
>>bad mainboard to bad disks, but none of them seem likely. Would it be
>>better if I would put the disks in the end of the IDE cables instead of
>>the middle one? Is somehow raidframe to blame here? I'm confused.
>I think you may have answered your own question.  If you have one drive on the 
>cable, and it's running in UDMA, it MUST be at the end of the cable.  If it's 
>not, the signal will not be stable (you basically have a big antenna hanging 
>off the drive).  This is documented in the ATA spec.
>You're more likely to lose in the RAID array because you're more likely to 
>have all of the drives active at once, and therefore have maximal