Getting around SATA cable length

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I've got an...unusual case. (Literally the case is weird. Photo below)



The tower is really designed to host two systems, but at the moment I only need one system in it, and would like to eventually populate all 16 bays. It's worked great, but I've run out of SATA ports on my motherboard and as a result I've started to look at some of the IT Mode SAS cards like the LSI 9201-8i for expansion, as you can break out to 4 sata connections per mini-SAS connector. Only problem I have is the length of SATA cables.


My understanding is that SAS cables are capable of running at greater lengths (up to 10m) vs the 1m limit of a SATA cable. My thought is that I could mount a breakout board/backplane in the drive chamber of the case using a couple of SAS connections that split into 8 SATA connectors I can branch off of. My only concern, is that it won't matter how long that SAS cable is if I'm running a SATA connection over it because that 1m limitation might still apply for the sake of signaling. I would hope to solve that by breaking out closer to the drives rather than at the SAS card but I'm pretty lost on how this works at this point.


I can't find a concrete answer to this elsewhere, but I figure there has to be a way to do it. Hell, maybe I'm barking up the wrong tree entirely and this doesn't make any sense at all.


Thanks in advance!

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If 1m from the motherboard/HBA isn't enough, you can run the longer SAS lengths between the HBA and a SAS expander (that you'll need to add).

From the expander you are then again limited to 1m for SATA.


In this scenario, make sure parity HDD and any SSDs connect directly to motherboard if possible, to ensure they get maximum bandwidth.

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Interesting. I'd guess SAS Expander is the search term I've been missing in my hunt for a workaround. The ones I'm seeing all seem to be PCIe cards though. Do they actually have any level of communication of the PCIe link or is it just being used as a power source for the card? If it's the latter, any idea if there's an expander that doesn't use PCIe?

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