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bxs

macrumors 65816
Original poster
Oct 20, 2007
1,140
515
Seattle, WA
Subject: OWC's Accelsior 4M2 PCIe M.2 NVMe SSD Adapter Card - Empty enclosure

After reading this -> https://macperformanceguide.com/blog/2019/20191220_1554-2019MacPro-OWC-Accelsior4M2.html that is dated 2019-12-20 it's stated this OWC card can be purchased for $249.99 empty.

Quote
The Accelsior 4M2 SSD is available now for pre-order at MacSales.com in capacities from 0GB (add your own drives) starting at $249.99, or from 1TB to 8TB with pricing starting at $519.99. It will begin shipping the week of December 30th.

FYI... I chatted with OWC today about this as their web site does not include the 0GB unit option and was told maybe it will be within next two months.
 

jasonmvp

macrumors demi-god
Jun 15, 2015
342
273
Northern VA
Again the question has to be asked: why gimp your fast, expensive NVMe drives by putting them in a half-speed card?
 
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bxs

macrumors 65816
Original poster
Oct 20, 2007
1,140
515
Seattle, WA
Again the question has to be asked: why gimp your fast, expensive NVMe drives by putting them in a half-speed card?
Yes, I understand why you say that.... but from my reviews comparing the data rates using the Sonnet/Samsung-blades x16 card vs. the OWC's Accelsior 4M2 PCIe M.2 NVMe SSD x8/x16 Adapter Card, I note there's little difference in their RAID-0 configuration data rates. The advantage of the OWC's card is that it can be inserted into a x8 or x16 PCIe slot. Not sure if the Sonnet card can also do this, even if it was desirable to do so.

Mind you, it has been reported here that the OWC card does exhibit weird data rates, but am unsure if this was with the previous OWC card that has now been removed from OWC's web site that cost quite a bit less.
 
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astrorider

macrumors 6502a
Sep 25, 2008
530
56
Subject: OWC's Accelsior 4M2 PCIe M.2 NVMe SSD Adapter Card - Empty enclosure

After reading this -> https://macperformanceguide.com/blog/2019/20191220_1554-2019MacPro-OWC-Accelsior4M2.html that is dated 2019-12-20 it's stated this OWC card can be purchased for $249.99 empty.

Quote
The Accelsior 4M2 SSD is available now for pre-order at MacSales.com in capacities from 0GB (add your own drives) starting at $249.99, or from 1TB to 8TB with pricing starting at $519.99. It will begin shipping the week of December 30th.

FYI... I chatted with OWC today about this as their web site does not include the 0GB unit option and was told maybe it will be within next two months.

It's currently $248.75 on B&H, but like the 1, 2, 4, and 8TB versions, it's listed as available in 7-10 days:
 
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tsialex

macrumors G3
Jun 13, 2016
8,944
9,524
Yes, I understand why you say that.... but from my reviews comparing the data rates using the Sonnet/Samsung-blades x16 card vs. the OWC's Accelsior 4M2 PCIe M.2 NVMe SSD x8.x16 Adapter Card, I note there's little difference in their RAID-0 configuration data rates. The advantage of the OEWC's card is that it can be inserted into a x8 or x16 PCIe slot. Not sure if the Sonnet card can also do this, even if it was desirable to do so.

Mind you, it has been reported here that the OWC card does exhibit weird data rates, but am unsure if this was with the previous OWC card that has now been removed from OWC's web site that cost quite a bit less.
You can install a switched card even on a x4 slot shared slot of a MP5,1. My SSD7101A-1 works with x4/x8/x16 slots, no problem, the Sonnet card has the same PLX PCIe switch. Obviously you are limited by the total throughput of the slot.
 
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Itconnects

macrumors regular
Jan 14, 2020
201
21
How do you know what configuration you’re getting when you select the ssd count or is it just the card alone for let’s say 949 4tb.
 
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bsbeamer

macrumors 68040
Sep 19, 2012
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2,077
How do you know what configuration you’re getting when you select the ssd count or is it just the card alone for let’s say 949 4tb.

There are four blades in each that ship with capacity. If you're looking at the 4TB model, divide by four for the capacity of each blade (4x1TB=4TB).

B&H still is listing the "empty" model for sale and now stating Mar 24, 2020 expected availability:
 
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Itconnects

macrumors regular
Jan 14, 2020
201
21
There are four blades in each that ship with capacity. If you're looking at the 4TB model, divide by four for the capacity of each blade (4x1TB=4TB).

B&H still is listing the "empty" model for sale and now stating Mar 24, 2020 expected availability:

So 1tb would be 250x4. Wish they would just put one stick with that order
 
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bsbeamer

macrumors 68040
Sep 19, 2012
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So 1tb would be 250x4. Wish they would just put one stick with that order

The ONLY way they can achieve those maximum advertised speeds is with RAID involved. No commercially available single blade can hit 6000MB/s.

Screen Shot 2020-01-22 at 12.00.24 PM.png
 
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bsbeamer

macrumors 68040
Sep 19, 2012
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Not sure for their specific blades, but most are rated around 1/2 that speed at theoretical maximum.

Samsung 970 PRO NVMe are rated at 3,500MB/s read and 2,700MB/s write.
Samsung 970 EVO NVMe are rated at 3,400MB/s read and 2,300MB/s write.

Samsung 960 PRO NVMe are rated at 3,500 MB/s read and 2,100 MB/s write.
Samsung 960 EVO NVMe are rated at 3,200 MB/s read and 1,900 MB/s write.

The NOT YET AVAILABLE 980 PRO is currently rated at 6500 MB/s read and 5000 MB/s write, but is a PCIe 4.0 device. Unsure what impact/hit would be with PCIe 3.0 adapter. Samsung says more information will be available in Q2 2020.
 
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tsialex

macrumors G3
Jun 13, 2016
8,944
9,524
Not sure for their specific blades, but most are rated around 1/2 that speed at theoretical maximum.

Samsung 970 PRO NVMe are rated at 3,500MB/s read and 2,700MB/s write.
Samsung 970 EVO NVMe are rated at 3,400MB/s read and 2,300MB/s write.

Samsung 960 PRO NVMe are rated at 3,500 MB/s read and 2,100 MB/s write.
Samsung 960 EVO NVMe are rated at 3,200 MB/s read and 1,900 MB/s write.

The NOT YET AVAILABLE 980 PRO is currently rated at 6500 MB/s read and 5000 MB/s write, but is a PCIe 4.0 device. Unsure what impact/hit would be with PCIe 3.0 adapter. Samsung says more information will be available in Q2 2020.
Still a M.2 device, so x4 PCIe device. So, a 980 PRO running at PCIe 3.0 speeds is limited to the theoretical maximum throughput of 3940MB/s that a x4 PCIe connection is capable, but real life is around 3400MB/s at best.

OWC blades are slower than Samsung 970 PRO blades for peak throughput and a lot slower with sustained throughput since it's TLC versus MLC NAND cells, after the OWC blade SLC buffer is full you get the real speeds for the TLC cells used.
 
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Korican100

macrumors 65816
Oct 9, 2012
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Still a M.2 device, so x4 PCIe device. So, a 980 PRO running at PCIe 3.0 speeds is limited to the theoretical maximum throughput of 3940MB/s that a x4 PCIe connection is capable, but real life is around 3400MB/s at best.

OWC blades are slower than Samsung 970 PRO blades for peak throughput and a lot slower with sustained throughput since it's TLC versus MLC NAND cells, after the OWC blade SLC buffer is full you get the real speeds for the TLC cells used.
with my limited understanding of NVMe tech, would you say the sustained throughput for the owc blades are higher than stock Apple storage?
 
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chfilm

macrumors 68030
Nov 15, 2012
2,961
1,721
Berlin
Again the question has to be asked: why gimp your fast, expensive NVMe drives by putting them in a half-speed card?
Well for example if you want to have an afterburner and two MPX modules, what other choice than sticking your SSD Raid into a x8 slot do you have anyway?

And I'm still wondering, in what kind of scenario would I need more speed than 6000mb/s ? Even on my 800 mb/s Pegasus Raid, the harddrive is RARELY the bottleneck during my video editing of 4k footage.
Way before that would become an issue, the sloppy decoding of h264 video in premiere would cap my performance. Ok sure, 8k Prores Raw might need such SSD speeds, but ...
If 6gb/s are enough, the 249 $ empty card would be quite a nice deal.
 
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jasonmvp

macrumors demi-god
Jun 15, 2015
342
273
Northern VA
Well for example if you want to have an afterburner and two MPX modules, what other choice than sticking your SSD Raid into a x8 slot do you have anyway?

Correct; that's a choice someone has to make. If they need all that video processing power, then x8 will have to suffice. And it's cool that we have that choice, too.

And I'm still wondering, in what kind of scenario would I need more speed than 6000mb/s ?

If your work flow doesn't involve pounding on the storage enough to cross 8GB/sec, then there's really nothing to worry about. As long as you're OK with the NVMe drives on that card being stunted, basically, from a performance perspective. If it doesn't matter to you, then all good. Your opinions and expectations are all that matter. Right?
 
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eric.blair

macrumors member
Sep 26, 2007
43
13
I chatted online with OWC twice earlier this week, spoke to a Robert I believe. He said there are no plans to release the empty card. I sent him this page OWC Digital Accelsior 4M2, which has since been taken down, the B&H page, and then their own Blog page and still he said those are errors and that he's asked for them to be removed. Their support reps need to get on the same page. In any case, I feel like they will still release the empty card at some point.
 
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chfilm

macrumors 68030
Nov 15, 2012
2,961
1,721
Berlin
I chatted online with OWC twice earlier this week, spoke to a Robert I believe. He said there are no plans to release the empty card. I sent him this page OWC Digital Accelsior 4M2, which has since been taken down, the B&H page, and then their own Blog page and still he said those are errors and that he's asked for them to be removed. Their support reps need to get on the same page. In any case, I feel like they will still release the empty card at some point.
I got a similar response from them three weeks Ago.
 
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bsbeamer

macrumors 68040
Sep 19, 2012
3,974
2,077
Part Numbers (Mac Pro 2010-2012 only + PC)
  • OWCSSDACC4M20GB
  • OWCSSDACC4M201T
  • OWCSSDACC4M202T
  • OWCSSDACC4M204T
  • OWCSSDACC4M208T
Part Numbers (also compatible with 2019 Mac Pro):
  • OWCSSDACL4M20GB
  • OWCSSDACL4M201T
  • OWCSSDACL4M202T
  • OWCSSDACL4M204T
  • OWCSSDACL4M208T
There is a "0GB" model for both.

BOTH have listings directly on their website:

With late March 2020 availability, not shocking their support isn't acknowledging this, but it's clear they at least intend to sell 0GB (empty) models.

-----

Here's their install notes with part numbers. Some points of interest below to help in the future:

-----
2019 Mac Pro Installs
Please note that the initial batch of Accelsior 4M2 drives have a heat sink that prevents the device from being properly installed in the 2019 Mac Pro. These models were given a specific part number that begins with OWCSSDACC4M2. Those models which will install normally on a 2019 Mac Pro were given the base part OWCSSDACL4M2 The part number groupings are shown below.

-----

2010-2012 Mac Pro Installs
Additionally, certain PCIe install configurations are not recommended or supported. Specifically, when certain double-width GPUs are installed in the bottom x16 slot (default / recommended), and the Accelsior 4M2 is installed in the neighboring x16 slot, either the GPU's shroud or its fans can contact one or more screws (or PCBA components) on the bottom of the Accelsior 4M2, causing potential problems. For this reason the XFX RX 580 cards sold by OWC — such as OWCMP1012R580V — cannot be used in conjunction with the Accelsior 4M2 in the above-noted configuration; the Accelsior 4M2 would have to be installed in one of the x4 slots higher up the logic board, which would result in reduced SSD performance.

The following commonly used double-wide GPUs have also been sold by OWC in the past, have been tested with the Accelsior 4M2 in the above dual x16 configuration, and did not make contact with the fans or other critical card components. If each card is installed properly according to Apple's PCIe card recommendations for these Mac Pro models, these configurations should work.

  • Sapphire Radeon 7950
  • Gigabyte Radeon RX 580 Gaming 8G
 
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Korican100

macrumors 65816
Oct 9, 2012
1,131
478
Does anyone here actually have and use this card? All this negative critique on the card, I’m interested in real world use and benefits. Especially from a video editing perspective
 
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bsbeamer

macrumors 68040
Sep 19, 2012
3,974
2,077
There are several reports in other MP7,1 threads for non-bootable usage (not system drive). Have not seen reports in MP5,1 or MP4,1>MP5,1.
 
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flygbuss

macrumors 6502a
Jul 22, 2018
665
1,192
Stockholm, Sweden
is the same junk +g*
I have two of the syba crest cards and they seem quite well made and perform flawlessly in slot 1 and 2 (x16)
Temps are never above 50 C though I should mentioned that the mac is inside a machine room with AC and 22 C.

I use the cards with WD black drives since the Samsung 979 evo plus wasn’t available at the time.
R/W speeds are between 2700 and 3000 MB/s.

The fans inside the cards might be audible but I can’t say much about the noise since the ambient sound of the room is louder.
 
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