Hi Hi, I need a housing for SATA hard drives with around 4 bays that can also be connected with SATA. Does somebody has any idea
Sry i like to using only sata no esata or no usb only sata
I am using some of these: ST-5255
I paid like 65€ and build quality is ok given the low price. The fans are a bit noisy so I replaced them with Noctua fans.
I see that they connect via SATA cables externaly. The SATA cables are designed to be used inside metal enclosures (PC cases, etc), because they lack the shielding that eSATA cables have.
I don’t know how big of a problem is, but shielding is there for a reason. Maybe they can interfere with other electronics, or throw errors to your system, if used externaly without a proper shielding. You should read into this.
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The black part is a nylon braid that has nothing to do with interference shielding. A shield is made of a conductive metal and grounded at (at least) one end of the cable. Those cables are at max length (per specs) btw.
You are right. It felt like metal but at a closer view it is not.
I was looking for a cheap solution and it works for me. Way better than my USB cases BTW.
There are shielded and unshielded sata cables, the eSATA are often shielded, but mostly it’s about different connector that can be securely attached.
Usually cheap short ones are unshielded, and I found it to be increasingly difficult to buy the ones that simply work. It feels everyone is competing on how to make a cable for two cents delivered while pissing off an acceptable amount of people. Most more expensive version of these cables are just the same shit cables with a higher price tag and a slightly less fake sounding brand name.
The solution here is to use old enterprise sata cables. They are almost always longer (often you have to route stuff inside the case around the motherboard) and shielded, and what’s more important, don’t suck.
That said, I would not worry about EMC even with unshileded cables. Sata uses differential signaling, just like Ethernet, and interference suppression is achieved by twisting the pair of conductors. There are cat 6 UTP cables that can transmit 10Gbps at the distance to 55 meters. Sata cables are nowhere near as long and the bandwidth is half.
As I said, 1m cables are the max according to the specs. That does not mean 1m cable + 20cm motherboard traces + 10cm pcb traces on the disk. That means the max cable length you should buy is < 1m. The next step down is usually 0.7m cables.
There is no such thing as enterprise sata cable. There is sata cable, and there are sas cables (which yes, can be longer since sas uses higher voltages). SAS can go up to 10m (well…) and to use a mix of drives you need interposers (signal converters) since the hba will default to sas signaling (interposers convert the sas signals coming from the controller to the sata signals for your drive).
No need to nitpick wording. The intent is “cables that can be found in old enterprise equipment”, as opposed to those you can buy on Amazon for $1. It has nothing to do with standards, just quality.
Again, nobody argues with the spec.
I’m not nitpicking on wording. The cable connector is different. They are different cables. sas drives have two channels (they are full duplex): one for sending, one for receiving and/or one running to one controller, one running to a different controller (high availability). sas drives have an extra “path” between the power and “sata” connector (that’s why there isn’t a divider between them in sas backplanes). That’s where the extra pins are. As you can see, you CAN plug in an sas cable into a sata drive, but not the other way around.
I don’t get it.
You brought up SAS, built a straw-man out of it, and are now got busy attacking it.
Nobody in this thread talked about SAS but you.
What’s is your point, on topic? To remind you, this detour was about EMC tolerance of UTP sata cables and merits of eSATA.
I’m correcting you. There isn’t any strawman. You can use sas cables if you stick to the sata specs if they are going to be used as sata cables. That is exactly what my previous comments said.
Please quote the part you are correcting, where I said anything about SAS, let alone the opposite.
You said enterprise sata cables. And you keep mentioning UTP cables, which I have not bothered to correct so far. The cables are not UTP, they are foiled and untwisted.
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Do you know how to quote on a forum? It’s not that hard.
So I take it you don’t have a quote of me you are fighting over. It was indeed a straw man you built.
Correct. Where is any mention of SAS?
Dude.
Take a cable. Take a knife. Remove the outer shell and/or shielding, if any. Behold the Twisted Pair inside and ponder on purpose and operation of differential signaling. It’s not just EMC but impedance consistency and many other factors that pretty much require it to be twisted.
Anyway. Unless you have anything constructive to say let’s close this detour.
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Behold the S/FTP cable that has been converted into UTP just for the sake of argument.
You are right. We should close this detour.