Mellanox ConnectX-3 on ebay look strange

Discussion in 'Great Deals' started by Stefan75, Oct 21, 2019.

  1. Stefan75

    Stefan75 Member

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  2. krista

    krista New Member

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    it appears these cages were to control airflow in a 1u ot 2u rack server. noisy little beasts of 40mm fans, sometimes 40x56mm!! and often shredding air at nearly 30,000 rpm while screaming like a constipated deamon child trying to pass yoko ono... while on fire. oh, and there's a large number of them. they're all blowing the same direction, usually front to back.

    as they spin so fast and are very thicc (heh) they create a *lot* of static pressure, which is necessary to move air in a very compact and filled chassis. the longer and thinner air channels get, the harder it is to push air through, and the more static pressure you need to get the job done.

    one *very* clever thing thermal engineers do while designing 1u systems is to balance and use the flow generated by these wee dangerous beasties† to cool everything without additional fans. you will notice heatsinks designed specifically ppl l
     
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  3. BeTeP

    BeTeP Active Member

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    Usually posters confirm the "greatness" of the deal (by communicating with the seller or just ordering a sample) before posting here.

    As for your question, in this case the seller is "confusing" because they are either stupid (used wrong stock picture by accident) or plain dishonest. The price is not that great either. So hard pass.
     
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  4. gzorn

    gzorn Member

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    I don't trust ads that have obvious BS in them. ConnectX-3 cards run at PCIe 3.0, not 4.0. Also, I think that the 341 is a mezzanine card. I second the hard pass.
     
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  5. Thomas42

    Thomas42 New Member

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    I got one. It is a mezzanine card mounted on an adapter.
     
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  6. BeTeP

    BeTeP Active Member

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    This depending on the brand (i.e. mezzanine card standard) could be interesting just for the slot adapter alone. Nice thing to have for testing and whatever purposes. Can you post pictures?
     
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  7. Rain

    Rain Active Member

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    That's interesting! Does the mezzanine "carrier" have a part number or any sort of markings on it?
     
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  8. RageBone

    RageBone Active Member

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    Please post pictures.
    Would love a HP flexlom Adapter ; D
     
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  9. matthew5025

    matthew5025 New Member

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    The one I've got was a MCX342A. They've used a OCP to PCI-E converter, but it's not perfect. If your PCI-E slot has a capacitor right below it, this won't work.

    s-l1600.jpg s-l1600 (1).jpg
     
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  10. BeTeP

    BeTeP Active Member

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    #10
  11. hmartin

    hmartin Active Member

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    I want to buy just the OCP to PCI-E adapter. Haven't been able to find one anywhere.
     
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  12. matthew5025

    matthew5025 New Member

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    Attached more photos for the curious :D

    There's a pic of the adaptor too, hope it helps in your search!
     

    Attached Files:

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  13. hmartin

    hmartin Active Member

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    The seller replied to my question and seems willing to discuss selling the OCP to PCIe adapter separately.

    Quantity and price are still unknown. I'm assuming people would want an OCP mezz to PCIe x8 version?
     
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  14. int0x2e

    int0x2e Member

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    Just out of curiosity, which OCP mezz cards are you guys trying to adapt to regular PCIe? I've got a couple of OCP based machines and most of my mezz slots are empty. It always seemed to me that regular PCIe cards were more cost effective, but I'm guessing there's something big I've been missing...
     
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  15. semidetached

    semidetached New Member

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    I grabbed one of these for a server that has an OCP slot to free up a PCIe slot, but it could be useful for anyone wanting a 40GbE ConnectX-3 Pro (for VXLAN or RoCEv2)
    Mellanox MCX345A-BCPN ConnectX-3 40GbE QSFP+ PCIe 3.0 x8 Network Adapter Card | eBay
     
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  16. BeTeP

    BeTeP Active Member

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    Often when I express genuine interest in some obscure and therefore relatively low priced item and start asking questions - my questions help the seller to discover item's true value and they raise the prices. So if the price is reasonable - I tend to buy first and ask questions later.
     
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  17. int0x2e

    int0x2e Member

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    I knew these exist but had only looked at the two port version, which costs closer to $100...
    At this price, they do make sense. Thanks for sharing!
     
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  18. JustinClift

    JustinClift Member

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    @matthew5025 Would you be ok to post some further pics of the mezzanine card itself?

    In the photo's above there don't seem to be any markings of Mellanox nor board identifiers (part/model #, etc). I've never used a Mellanox mezzanine board before, so no idea if that's normal for them. With their PCI-E ones though, they normally have clear markings.

    Really curious about the OCP to PCI-E adapter too. In the UK and Australia, the mezzanine cards are almost always cheaper on ebay (sometimes by a lot) compared to the PCI-E ones. Having a supply of those adapters - especially x8 or x16 - could open up some possibilities. :)
     
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  19. hmartin

    hmartin Active Member

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    OCP mezz cards are PCIe x8, there is no x16 mezz card to my knowledge.

    The seller replied that for QTY 50, they wouldn't sell the OCP to PCIe adapter for less than the current price of the single port card ($22 USD + S&H) and they're not interested in listing the adapter separately.

    So buying the adapter from them is not an economical option.
     
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  20. JustinClift

    JustinClift Member

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    Interesting. But they'd be willing to sell the adapter (x4, or x8?) with a minimum qty of 50? If so, what price (in total) for the 50?

    If the adapters seem legit + price is reasonable, we might be able to split costs or something. :)
     
    #20
    Last edited: Oct 31, 2019
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