Intel Xeon D-1500 Series Discussion

Patrick

Administrator
Staff member
Dec 21, 2010
12,380
5,522
113
mirculix wrote>"... Plug an AOC-SLG3-2E4 into the PCIe 3.0 x16 slot, connect up to four NVMe 2.5" drives ..."

That card provides for two, not four, connected NVMe 2.5 in SSDs. The card has two, not four, SFF-8643 connectors.

The idea was to use the riser card, mentioned by Karl G, in the SINGLE x16 Intel D motherboard slot to provide for TWO AOC-SLG3-2E4R (the R version is less expensive) x8 card connections.
"... bifurcation worked to split the Xenon D motherboard's single x16 gen 3 slot to two x8 gen 3 slots, and each of your two x8 cards were seen as separate two devices."
Here is a link to the card Karl G said he used:
ARC1-PELY423-C7
I do not know if it would work. I would very strongly advise non-R versions for this if you did try it.
 

Kal G

Active Member
Oct 29, 2014
160
44
28
42
I do not know if it would work. I would very strongly advise non-R versions for this if you did try it.
I agree. Using the suggested riser card will split it into two x8 PCIe lanes. Using the R version of the card would require the riser to split it into four x4 lanes. The card is not set up to do more than a 2-to-1 split.
 

iq100

Member
Jun 5, 2012
71
3
8
Patrick & Kal G, please help me understand this.

Patrick and others had reported that the R version worked in SOME Supermicro motherboards. Allegedly those that supported bifurcation by the motherboards BIOS and hardware. I believe Patrick confirmed that the more expensive non-R card was only needed sometimes, allegedly for motherboards without integrated bifurcation capability.

I assume that the Supermicro's Intel D motherboards are ones that have bifurcation. That is why Kal G's riser card's two x8 slots were seen as two separate devices. I believe he successfully used this for two RAID cards?

So if the Supermicro Intel D motherboard's bifurcation capability is like the ones Patrick, and others, tested to work with a single R card, then the motherboard successfully split a single motherboard slot into the two x4 gen 3 lanes needed by two connected Intel 750 NVMe SSDs? If the riser card simply provides two x8 slots, seen as two separate devices, by the motherboard's bifurcation, why would motherboard bifurcation not work for both riser supplied x8 slots, each populated with a R card?

Maybe the Supermicro motherboards that have bifurcation capability are limited to split a single x16 or x8 slot to two x4 slots, and cannot bifurcate two slots? I wonder if someone has the hardware in place to actually test the riser card, 2 R cards, and 4 Intel 750 NVMe 2.5 in SSDs? I guess the testing could be in steps.

First see if a R card with two Intel 750s works in the single x16 Supermicro Intel D motherboard without the riser card. Together with an M.2 adapter with provides a SFF-8643 mini-SAS HD connector, that would allow for a three NVMe SSD Raid-0 setup in a small footprint case.

Second plug a single R card into one of the riser card's x8 slots. Kal G says this will break the ability to use two Intel 750s, because the motherboard bifurcation capability 'has been used up' by the riser cards two x8 slots, and the riser card has no ability to use two sets of x4 lanes on one of its x8 slots, breaking the use of two Intel 750s.
 
Last edited:

Kal G

Active Member
Oct 29, 2014
160
44
28
42
The reason it won't work is because the AOC-SLG3-2E4R bifurcates the PCIe x8 slot into two x4s. When you plug it into another bifurcation adapter, only the first SFF-8643 will work since there are only two control signals available from the motherboard. Both those control signals are split by the first bifurcation adapter. A second adapter, in series with the first, won't have an additional control signal to work with for the second SFF-8643 connector.
 

Kristian

Active Member
Jun 1, 2013
347
83
28
The capability is given in the name, isn't it? BIfurcation. bi = two, not four
I am not shure that this assumption is correct.
One of my Asus boards has the option to chose from the following options under the BIfurcation: 8x8, 4x4x4x4

But I have never used the option
 

Davewolfs

Active Member
Aug 6, 2015
337
31
28
Davewolf, read Karl G post where he wrote>"... bifurcation worked to split the Xenon D motherboard's single x16 gen 3 slot to two x8 gen 3 slots, and each of your two x8 cards were seen as separate two devices."
The case still has 1 physical slot to screw into. Even if you split then what? Just let the cards dangle inside the case :)
 

Davewolfs

Active Member
Aug 6, 2015
337
31
28
IS it safe to assume that Xeon D 1540 does around as well or better in single threads as say an i7 920/950/970?
 

Kristian

Active Member
Jun 1, 2013
347
83
28
"News" from Asrock:

Code:
Hi Kristian, 
I am afraid D1540D4I is out of stock at this moment. 
If you can wait a bit longer there will be available after 3-4 weeks. 

It needs to be SoC? 
otherwise you can consider EPC612D4I or C27504I if its urgent! 
Thanks ASRock Rack marketing team
 

cheezehead

Active Member
Sep 23, 2012
723
176
43
Midwest, US
"News" from Asrock:

Code:
Hi Kristian,
I am afraid D1540D4I is out of stock at this moment.
If you can wait a bit longer there will be available after 3-4 weeks.

It needs to be SoC?
otherwise you can consider EPC612D4I or C27504I if its urgent!
Thanks ASRock Rack marketing team
AKA sorry we advertised vaporware....Try the EPC612D4I (oh wait that's vaporware as well)...Or try the C27504I ( I think you mean the C2750D4I but it doesn't have the umph to handle your workload).
 
  • Like
Reactions: Kristian