[geeks] ATA vs. SCSI

[Mark]

On 5 Jun 2007, at 06:10, Dr Robert Pasken wrote:

> Strange , I've never had any luck with IDE/ATPAI/PATA/SATA drives.

The first 3 I can understand but SATA? Where exactly can you  
experience problems with that? You just plug the darn thing in and it  
works, tho occasionally you have to enable it in the BIOS.

> Trying to add more than one requires sacrificing three vestal  
> vigins, two
> graduate students and a partridge in a pear tree.

You quickly learn to stick to like devices on a ribbon with PATA/ 
ATAPI. e.g. pairing a hard drive with a CD drive is asking for bad mojo.

> SCSI just requires that the header jumpers be different, plug in  
> the signal and power cables
> and it works.

Explaining to Joe user how to set SCSI jumpers is a nightmare. This  
is not totally down to the fact they are complex (i.e. they use  
binary etc.) but also because there are a lot of them and they are in  
different places on different vendors disks. Also on some systems  
certain SCSI IDs are 'reserved' (i.e. they aren't stonewalled but you  
aren't 'supposed' to use them, and on some OFW machines it makes  
booting 'interesting') for certain classes of device, which causes  
even more issues.

SCA is a godsend for this, but it doesn't usually easily accommodate  
non hard drive devices.

> What is it with cable select, master, slave, cable with a twist,  
> none of which are consistent even with the same manufactuer.

I've found hard drives from vendors are pretty consistent, but  
Optical drives aren't. I take you're point though when it comes to  
using different vendors drives. I recently had to fit a second disk  
in my Dell Dimension 4600 (my until recently work desktop). Western  
Digital use a totally different jumper pattern to Seagate. Very  
confusing...

> Just bought a 300gb 15rpm Fiber channel drive on ebay for $150,  
> plug it into
> the backplane and it works. Try that with a SATA drive

Erm... I just plug SATA drives into my Mac Pro and they work... using  
a Backplane... Same with SAS disks. If you are having issues with  
SATA you really need to get something looked at (I mean the computer  
not ya heed :) ).

-- 
Mark Benson

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