[G4] EIDE and Ultra ATA RAID

[Philip J Robar]

On Apr 24, 2005, at 5:55 PM, Kevin Willis wrote:

> I have been using a 120 GB Western Digital EIDE drive in my G4 for  
> about a year.  I also have 2 40 GB Ultra ATA drives installed.  I  
> recently picked up a 120 GB Ultra ATA Seagate drive that I put in  
> place of one of the 40 GB drives.
>
>  I am planning on setting up a Striped RAID using the 2 120 GB  
> drives and installing Tiger on it.  Is this possible even with the  
> 2 different interfaces?  If it is possible, would it be worth  
> spending another $80 or $90 to get another Ultra ATA drive to use  
> in place of the EIDE drive?

"EIDE" and "Ultra" are names made up by marketing types. ATA is the  
official spec. Your EIDE drive is an ATA drive. Search the web if  
you'd like details.

Yes, you can stripe them, but be aware that this increases your  
chance of data loss due to hardware failure - if either drive fails  
you loose all of your data. Also stripping does not provide a  
performance benefit for typical single user desktop installations.  
For details see AnandTech, http://www.anandtech.com/storage/ 
showdoc.aspx?i=2101. Quoting from the article's conclusion:

     If you haven't gotten the hint by now, we'll spell it out for  
you: there
     is no place, and no need for a RAID-0 array on a desktop computer.
     The real world performance increases are negligible at best and the
     reduction in reliability, thanks to a halving of the mean time  
between
     failure, makes RAID-0 far from worth it on the desktop.


On Apr 24, 2005, at 9:04 PM, Johns Maillist wrote:

> The best idea is to buy another Serial ATA drive, add it to the  
> system, STRIPE the two SATA drives!

Kevin said nothing about having a serial ATA drive. Unless he says  
otherwise, I'm assuming that all of the drives he has have parallel  
ATA interfaces.


Phil