AEC-6890M 2-CH SATA RAID Adapter for Mac

[jasonrudolph]

Anyone tried this
http://www.mars-tech.com/aec-6890m.htm

It doesn't look like its pci-x though

[samsc]

Jason.
I split your thread...

This is an internal only sata adaptor - one which has external ports might be more useful.
Not many specs shown here.
Its not worth getting something like this - unless it has external ports, as turning both internal drives into a raid set isnt a good idea.
Fundamentally you have to keep your content separate from the Operating system - physically separate - a separate disc:


Christian choi did a lot of playing around with sata raids.

[jasonrudolph]

Jason.
I split your thread...

This is an internal only sata adaptor - one which has external ports might be more useful.
Not many specs shown here.
Its not worth getting something like this - unless it has external ports

Yes, but you can now get internal to external adapters from MacGurus
http://www.macgurus.com/productpages/sata/satakits.php
(scroll to bottom of the page)

In fact, I missed this card
http://www.macgurus.com/productpages/RAID/SyncRAID.php

says there should be a 64bit card in spring of 05.....

[samsc]

im not a fan of sata drives in these kindof cases.
sata connectors are horrible.

but if someone can make it work then its worth a try.
But bear in mind that the headline data rate does nothing - nothing at all.
Its the drive latency and seek times that are important with multiple layers.
drive latency and seek time do not reduce with multiple drives in this configuration - if you are really lucky they will increase.

But do not ever try and use one of those horrible internal drive adaptors like the G5 jam - they really dont work - and arent 'movable' -let alone tourable.

[jasonrudolph]

im not a fan of sata drives in these kindof cases.
sata connectors are horrible.

but if someone can make it work then its worth a try.
But bear in mind that the headline data rate does nothing - nothing at all.
Its the drive latency and seek times that are important with multiple layers.
drive latency and seek time do not reduce with multiple drives in this configuration - if you are really lucky they will increase.
.

Since this is a Hardware RAID card, how is this different that the RAID controller used in an XSERVE RAID for instance? I undersatnd the drive latency is what is important, but once again, what is the difference compared to what is used in an xserve RAID? I thought they were just average, run of the mill drives in there.

[samsc]

no specs given on ACARD hardware raid
I dont have any idea how well any raid system will work until its tested.

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Xserve RAID has a 512MB cache/channel.
Each Xserve RAID has dual channels. And uses Fibre Channel as its interface.

It is a totally different beast from the ACARD pci card here.

But I only know it works because I tested one. Nothing in the specs indicates 'a priori' that this will work with well Catalyst.

http://www.apple.com/xserve/raid/

Setting this up and making it work was MUCH easier than i expected.

[samsc]

Jason.

Are you going to buy one of these and give it a try?

Richard

[jasonrudolph]

Jason.

Are you going to buy one of these and give it a try?

Richard

Am Seriously considering it.

[samsc]

If you get one, ill send you a document showing how to do automated performance self testing in the software.
then we can add this to the performance graphs i made early last year.

[samsc]

8 port sata card:

http://www.sonnettech.com/product/tempo-x_esata8.html


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I just dont get the use of sata for this- it is not designed to do this kindof thing.
sata connectors are really really horrible.