ConnectX-3 direct connect to ConnectX3, Type A or Type B Cable?

[Deano]

When buying a replacement cable to try and get my ConnectX-3 to ConnectX-3 direct connect between two computers working should my MPO/F to MPO/F cable be type A or type B?



My cable which i suspect doesn't work, I have no idea which type it is as the official websites page doesn't seem to work ' Prolabs OM3-24C-MPO/F-13.72M' Fibre Optic Cable

 

[rtech]

Type B. I have CX-3 to CX-3 connection.
For 40G you need typically need 12 fiber MPO cable depends on transceiver though.

btw that cable you got is 24 fiber/core MPO cable?

 

[Deano]

The one I have was listed as Prolabs OM3-24C-MPO/F-13.72M , I think it's 24 core, I'm still not sure if it's the problem part as i don't have duplicates of anything.
I can't seem to find any on ebay like that one though as a replacement (plus the prices on Ebay for these things has shot through the roof!) the only ones i can seem to find are 8 core and 12 core. It's all a bit of a mess really

 

[rtech]

You sure that fiber does align in transceiver and in cable?

 

[Deano]

I can't be sure, but I have tried to plug in the transceivers a few times on different days, I tried using the other port too in each card. Then on seperate days i've tried putting the cable in again, today I even tried to layed the cable out flat and swapped which end is plugged into which PC, Still reports Cable Unplugged every time.

 

[prdtabim]

When buying a replacement cable to try and get my ConnectX-3 to ConnectX-3 direct connect between two computers working should my MPO/F to MPO/F cable be type A or type B?

View attachment 30053

My cable which i suspect doesn't work, I have no idea which type it is as the official websites page doesn't seem to work ' Prolabs OM3-24C-MPO/F-13.72M' Fibre Optic Cable

I used type B cable with this transceiver.

Mellanox MC2207411-SR4L 56Gb 30m FDR Infiniband/40GbE QSFP Transceiver Module | eBay

Such as SFP/ SFP+/SFP28/ QSFP/ QSFP28/ CFP/ HBA / Network Card/ Raid Card/ Expander Card/ AOC/ DAC/ Raspberry Pi etc. All the products manufactured strictly carry out international and national relevant technical standards.

www.ebay.com

with " 3M MPO Cable 12 Fiber OM3 Type B MPO-MPO Famale Multimode 3mm Fiber Patch Cord " .

3M MPO Cable 12 Fiber Famale Multimode Type B OM3 3mm Fiber Patch Cord | eBay

Compatible with fiber optic modules which support OM3. Compatible: Transceivers which support OM3. Connector Type: MPO Type B. Such as SFP/ SFP+/SFP28/ QSFP/ QSFP28/ CFP/ HBA / Network Card/ Raid Card/ Expander Card/ AOC/ DAC/ Raspberry Pi etc.

www.ebay.com

 

[Deano]

I took a couple of quick pictures, they seem to be seated right
upstairs

downstairs

Thank you for the links, I think I need to get a 13 meter cable if I want to run the cable up a wall and down the other side safely, I was planning to run it under a Cable Concealing&Protecting Floor mat, but after having one break already having it running up the wall seems safer than the floor, these prices you linked seem really good compared to what I was seing on the Ebay UK site, i'll have to see what shipping is like

 

[klui]

If they're less than a couple of meters away from each other just use a DAC cable. If you must use fiber, OM3 8 core is enough.

 

[Deano]

unfortunately it has to travel all the way up these stairs and then a small distance back into this room I was planning to use the circled floor cover, but I think up the wall will be safer.

 

[klui]

I just noticed you mentioned you have a 24-fiber cable. They won't work on most transceivers. 40G transceivers typically have 1 row of fibers and if you inspect them they have holes for 8. 24-fiber cables have 2 rows of 12 fibers so fibers won't align. The following describes 100G but the top applies to 40G http://www.fiber-optic-transceiver-module.com/wp-content/uploads/2016/07/cable-connector-options.jpg

Just get some Brocade FC transceivers for ~US$7 and they will work at 40G. @fohdeesha mentioned them in this forum.

 

[Deano]

I have no idea which cable type the Finisar FTL414QL2C-E5 QSFP 4X14Gpbs use, but i think i was given a direct link to the transcievers and cable at the same time and told to buy them together, so maybe the 8 and 12 wouldn't even fit it, this kinda makes things more difficult as it now could be broken cable or incorrect cable.

Windows 10 with and WinOFT also bluescreens on start with ConnectX3 and Alder lake E-cores turned on with something like Mlx4.sys as the listed reason, so i've been running with all my E-Cores off just trying to get the connection working.
I'm starting to wonder if the confirmed WinOFT2 and Connectx-4 cards which are confirmed to be working with my E-Cores turned on due to being on WinOFT2 might be the better choice if i'm replacing Cables and Transceivers and over 50% of the whole network system.

I wonder how much a full ConnectX-4 set will cost and what i'm looking for.

 

[rtech]

Why dont you test the cable?

DO NOT LOOK INTO MPO CABLE TERMINATION TO SEE LASERS
Turn off lights in room and point the MPO cable somewhere you should see the lasers. If you dont cable/transciever coupling doesnt align.

At least i was able on my MMF OM4

 

[Deano]

I made the room upstairs as dark as possible, couldn't see anything up against the white wall in a dark room, everything just remained dark.

 

[rtech]

100G MMF/SR transceivers also require 12 fiber MPO cable.
Or get the Intel one mentioned on STH main site which takes LC cable...

Edit: added link to transceiver 100G OS2

SPTSBP2CLCKS INTEL 100G-CWDM4 1271-1331NM OPTICAL TRANSCEIVER MODULE NEW | eBay

Find many great new & used options and get the best deals for SPTSBP2CLCKS INTEL 100G-CWDM4 1271-1331NM OPTICAL TRANSCEIVER MODULE NEW at the best online prices at eBay! Free shipping for many products!

www.ebay.ca

 

[Deano]

The only intel thing i could see going to the network part of the main site was https://www.servethehome.com/silicom-p4cg2bpi81-dual-port-100gbe-intel-e810-bypass-adapter-review/ I'm assuming this is new and expensive.

I just want to connect two computers at home, I'm unlucky, I got the connectX-3, the transceivers and the cable someone directly told me to get, and not only is something wrong with the hardware I happened to purchase, it also blue screens on windows with exactly the make and model of processor i go with. I have to say again I'm very unlucky.

I'll try this 15 meter MPO 12 Fiber Cable for a small amount of money, hopefully it works, and I'll just have to try and do most of what I do on Linux, which doesnt blue screen with the setup i have now with the E-Cores turned on. So it's purely a driver/windows problem, it's just i like the choice dual booting gives me, but now i have to visit the bios and turn off a bunch of cores or leave them off.

 

[klui]

Just disconnect everything and look at the ends of the transceiver and MPO connector. It's not that hard. STH's main site articles show them.

https://www.servethehome.com/wp-content/uploads/2021/12/MPO-MTP-Male-Female-Connectors-Right-Facing-2-696x509.jpg

https://www.servethehome.com/wp-content/uploads/2021/09/100GBASE-SR4-Module-Close.jpg

 

[Deano]

Here you go, the cable is two "rows" and one "hole" at either end. (All 4 Pictures slightly different angles, Camera wouldn't focus)



transceiver is one "row" and three "holes" at either end. (2 different pictures, both of these came out clearer)



Do i have the wrong cable? the wrong cable all along?

 

[klui]

Most likely wrong cable. Cable photos are too blurry. Use macro or take photos farther away then zoom in.

 

[Deano]

My cable just came in from China and when plugged in immediately worked and the network is up and running! (12 core, 20 meters, £37)

Thank you to everyone:
Rtech you were right in You first post my 24 core cable was the wrong fit.

prdtabim thank you for saying to get a B type cable, that one worked, i really couldn't understand which one i needed on my own! I also would have tried using UK sellers which would have cost me over double the money, thanks to using ebay.com and watch listing the item and then flipping back to the ebay.co.uk site you saved me a bundle.

klui thanks for teaching a man to fish, now i know why my cable was wrong because of the two rows on the cable but only one row on the transciever. Learning what went wrong is a huge help understanding what might be wrong next time!