From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Bevand <bevand_m@epita.fr>
Subject: Re: SATA chipset recomendations
Date: Wed, 09 Jun 2004 17:37:24 +0200
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David Greaves wrote:
> I have wondered whether I'd have been better off with 2x Promise TX2s?
> I don't know where the bottleneck is with 4xSATA disks on a single 
> Promise/PCI slot

I have 4 x Seagate 160GB SATA connected on a Promise SATA150 TX4. The
bottleneck is always the PCI bus:

  o 66 MHz PCI bus (266 MB/s): I reach 209 MB/s (79% of theoretical bandwidth)
  o 33 MHz PCI bus (133 MB/s): I reach 100 MB/s (75% of theoretical bandwidth)

Note: each disk is able to generate a datas rate of about 57 MB/s.

-- 
Marc Bevand                          http://www.epita.fr/~bevand_m
Computer Science School EPITA - System, Network and Security Dept.