On Thu, 26 Sep 2002, Sean Farley wrote:

> I just do not understand how a 5400 RPM UDMA 33 drive can beat a 7200
> RPM UDMA 133 drive by 33% on sequential output blocks.

Rumor has it that newer drives cannot write a single sector at a time, and
instead must read a whole cluster of sectors, add in the new sector, and
write back the whole cluster.  That behavior sounds like it would hurt
sequentual performance substantially, as it would become a lot of
read-modify-write operations.

> > Does the drive support tagged queueing?  That should give you the
> > benefits of write caching with a little bit more safety.
>
> I thought only IBM had IDE drives which supported tags.  No.  The specs
> do not mention tags.

Hm, I thought other vendors had started to support them, I guess they
decided not to. :|

I have no idea on what BIOS settings would be optimal.  I doubt that
they'll make a real performance difference.

Mike "Silby" Silbersack


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