How are you powering the four drives in the optical bay? Some sort of SATA power splitter hooked up to the optical bay's SATA cable?
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USB 3.1 PCIe for cMP info repository
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How are you powering the four drives in the optical bay? Some sort of SATA power splitter hooked up to the optical bay's SATA cable?
The photo shows the back of the optical drive bays with a BD/DVD drive placed in the upper bay and Icy Dock in the lower bay.
The cable connections are straight forward.
Icy Dock’s power is taken out of the mid section of the cable that goes to the BD/DVD drive and fed to the power connector of Icy Dock. The splitter data cables, labeled as P1 to P4, come from one of two SAS connectors on the RAID controller board. They are connected directly to four data ports of Icy Dock in which four SSDs are placed.
The model I used is ExpressCage MB324SP-B which you can find here:
http://www.icydock.com/goods.php?id=196
I understand a few members have the caldigit FASTA-6GU3 PLUS card on a 5.1 MP.
Can anyone please inform me if this card actually works as USB 3.1 10Gbps with the new firmware on Sierra?
After searching I can't find to find a definitive answer.
If there is an answer I missed I apologise.
Posts 215/216 indicate that the Caldigit after firmware update still reports itself as 5Gbps in System Profiler, but when measured it has throughput higher than 5Gbps could possibly provide. Personally, this is the only report I've seen of anything higher than 5.
Thanks for your answer ActionableMango!
I was hoping on a longer running test to prove that those speeds are attainable at sustained copy/write operations.
I have read here that many times these speeds tend to slow down significantly and I need this card for big file transfers.
I just don't want to spend the money to have the card be useless for me.
Perhaps zoomfinder can chime in on this...
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Okay thanks so much for the info!
If available, would you please post a link for where the SATA power splitter was/can be purchased?
Also how are you routing the data splitter cables from the PCI bay into the optical bay?
I've posted my testing results of a “StarTech.com 2-Port USB 3.1 (10Gbps) Card – 2x USB-C – PCIe (PEXUSB312C)“ at
https://pikeralpha.wordpress.com/2016/11/10/two-port-usb-3-1-gen-ii-pci-express-card/#comment-8757
It uses an ASM1142 chip configured as PCIe gen 2 x2, even when used in a PCIe gen 3 slot. I think this is decided by the manufacturer, and not by the slot. I don't think there's a PCIe negotiation method that can switch between PCIe gen 3 x1 and PCIe gen 2 x2.
The USB speed usually reports as "Up to 5 Gb/sec" in System Information.app, even though it transfers at faster than 5 Gb/sec. I believe this is a bug in Asmedia chips in general. The status register that reports the speed is not updated correctly. This is discussed in that post I linked. AlpineRidge chips (Thunderbolt 3) have better USB 3.1 gen 2 behavior.
I inserted the card into an old Mac Pro. For extra power I used these 3 cables (extra power is not required):
4-Pin Molex to 2x Molex Splitter Cable - 20cm
4-Pin Molex Extension - 90cm
4-Pin Molex to 2x SATA Power Splitter Cable
I had to take out the DVD enclosure, the front fan assembly, and I had to unscrew the SATA connector of the first drive bay to fish the extension cable through. The molex splitter fits behind the DVD drive enclosure when you put everything back together again.
https://pikeralpha.wordpress.com/2016/11/10/two-port-usb-3-1-gen-ii-pci-express-card/#comment-8757
It uses an ASM1142 chip configured as PCIe gen 2 x2, even when used in a PCIe gen 3 slot. I think this is decided by the manufacturer, and not by the slot. I don't think there's a PCIe negotiation method that can switch between PCIe gen 3 x1 and PCIe gen 2 x2.
The USB speed usually reports as "Up to 5 Gb/sec" in System Information.app, even though it transfers at faster than 5 Gb/sec. I believe this is a bug in Asmedia chips in general. The status register that reports the speed is not updated correctly. This is discussed in that post I linked. AlpineRidge chips (Thunderbolt 3) have better USB 3.1 gen 2 behavior.
I inserted the card into an old Mac Pro. For extra power I used these 3 cables (extra power is not required):
4-Pin Molex to 2x Molex Splitter Cable - 20cm
4-Pin Molex Extension - 90cm
4-Pin Molex to 2x SATA Power Splitter Cable
I had to take out the DVD enclosure, the front fan assembly, and I had to unscrew the SATA connector of the first drive bay to fish the extension cable through. The molex splitter fits behind the DVD drive enclosure when you put everything back together again.
So has anyone tried these Ableconn cards - on Amazon now they are listed as 3.1 Gen2, with 2 x type A, 1xtype A and 1xUSB-C, or 2 x USB-C port options. All claim OSX 10.12 compatibility without drivers, and Win 8/10 without and Win with drivers. As they are $31-$37 depending on ports, I'd buy one to test as a replacement for my Newertech Legacy USB3 A and eSata card, but they don't ship to Finland...
EDIT - just seen that you (Slash-2CPU) are/were using this card, was it an older version not marketed as 3.1 Gen2, or is there a reason you can see it's not hitting Gen2 speeds?
510 MB/s is faster than USB 3.0 gen 1. It looks like the speed of one SSD. You need a raid of two SSDs to get the max USB 3.1 gen 2 speed (around 845 MB/s).
The 3.0 card looks like x1.
The 3.1 card looks like a Asmedia 1142 based card (like Startech and Caldigit use). Ellectrically PCIe 2.0 x2 even though they are physically x4. x2 cards may behave as x1 in some PCIe slots.
The Caldigit is a PCIe 2.0 x4 card so a USB port will have the same performance in a PCIe 1.0 slot as a PCIe 2.0 slot (USB gen 2 speed requires Sierra, which requires an installer patch to work on Mac Pro 2008).
Read my post about PCIe x2, Startech and Caldigit at #1801
You won't get more than about 340MB/s per PCIe lane on a 2009/2010 cMP. So max that the card could push into the cMP's slot is 650-675MB/s. I tested using an enclosure with a Samsung 840 Pro that can hit 520/550 read/write when plugged into my Win10 machine, so 510MB/s is not quite the limit of the enclosure/SSD. Could be that MacOS is less efficient with USB transfers.
You could use a RAID0 enclosure, if you really desperately need that last 150MB/s. You also need an external power brick at that point, so it's much less portable.
If you're breaking 500MB/s over USB on a cMP, you're doing pretty good. With the exact right setup, you can get 650+MB/s, but the price/performance to get that last 100-200MB/s isn't worth it for me. Most of what I'm transferring to/from on the USB side can't sustain 400+MB/s anyway. I'm usually moving 3d point cloud files on 850 Evo's. One job's worth of files runs 250-720GB. After the first 30-60GB at 500MB/s, the SLC buffer fills up and they drop to 150-250MB/s.
As far as I've seen with Sierra and the current crop of SATA-USB chips, it's hard to get Gen2 to work reliably for 100+GB transfers. Some won't ever link at 10gbps while others overheat and drop out.
Does anyone know where I can download this or if I even still have to? I'd like to get the USB 3.1 speeds on my Mac Pro 5,1. Seems like it's working at 5Gb/s right now.
Edit:
Thanks me.
Does anyone know the link to the 5Gb/s now in case I have to revert?
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