Dont judge me.....gigabit PCI fiber NIC with at least one SFP connector?

Smoblikat

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So for various reasons I am in the market for a fiber NIC that connects over a PCI bus. Has to be gigabit fiber, I saw a couple (overpriced) cards that did 100mbps, but I would definitely need to have the full gigabit (PCI does 133MB/s I think, gigabit should be around 125, no clue why this is so hard to find). Does anyone have any recommendations on cards that fit this spec?

I found this:
https://www.newegg.com/intel-pwla8492mf/p/N82E16833106203

and while it is a PCIx card, assuming I only populate one of the SFP's with a GBIC, I should still be within the maximum bandwidth available from a regular 32 bit PCI bus.

Anyone have any better options I should look at?

Thank you,
Smoblikat
 
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sinisterDei

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Smoblikat

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I am confused as to why you think you need the thing you think you need.

First off, https://www.newegg.com/transition-networks-n-gsx-sc-02/p/N82E16833350036 exists on Newegg. It looks to be essentially what you want.

With that said, it might be easier to get a regular RJ45 gigabit NIC in the system and use a media converter to convert from fiber to copper. Something like this: https://www.newegg.com/tp-link-mc220l/p/177-000H-00001
That card is an SC style connector, I need an SFP port that accepts an LC GBIC because thats what the rest of my network uses. I already have a media converter, and I have exactly 1 PCI slot left in the server, im just looking to play around with another fiber card. I can find the one I linked in the OP for around $25 on ebay, seemed cheap enough to try out, but I wasnt sure if there was a newer (or hopefully regular 32 bit PCI) card out there that fit the bill.
 

sinisterDei

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From your post I was under the impression you required regular old 32-bit PCI. As you pointed out the card you linked is PCI-X, and I'm not sure if it's one of the ones that are compatible with a 32-bit slot (not all of them are). Given your wording I'm assuming you only have a 32-bit slot available. Assuming it does work in 32-bit, it'll be an inexpensive way to get your desired result if you can buy it for $25 + a reasonably priced GBIC. Alternatively, the card I linked plus a SC->LC adapter kit should also work.

You may be running into trouble finding the exact card you want (32-bit PCI with a gigabit SFP) because there just isn't a large time period when the SFP form factor existed (introduced in 2001 or so) and standard PCI was in use (PCIe came out in 2003 and was rapidly adopted). Given the lack of benefit of moving to fiber (since any speeds >1Gbps were limited by a standard 32-bit PCI bus, the fact that regular RJ45 gigabit PCI cards were commodity by that point), as well as the existence of PCI-X for servers, the card you want may just not have existed much or at all. It's certainly not something I ever ran into in my years.
 

Smoblikat

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From your post I was under the impression you required regular old 32-bit PCI. As you pointed out the card you linked is PCI-X, and I'm not sure if it's one of the ones that are compatible with a 32-bit slot (not all of them are). Given your wording I'm assuming you only have a 32-bit slot available. Assuming it does work in 32-bit, it'll be an inexpensive way to get your desired result if you can buy it for $25 + a reasonably priced GBIC. Alternatively, the card I linked plus a SC->LC adapter kit should also work.

You may be running into trouble finding the exact card you want (32-bit PCI with a gigabit SFP) because there just isn't a large time period when the SFP form factor existed (introduced in 2001 or so) and standard PCI was in use (PCIe came out in 2003 and was rapidly adopted). Given the lack of benefit of moving to fiber (since any speeds >1Gbps were limited by a standard 32-bit PCI bus, the fact that regular RJ45 gigabit PCI cards were commodity by that point), as well as the existence of PCI-X for servers, the card you want may just not have existed much or at all. It's certainly not something I ever ran into in my years.
Correct, sorry if the wording was confusing. I have one standard length 32 bit PCI slot left, and am just going to hope the card works in it, I found one for under $20 and grabbed it :D

Really good point about the difficulty of finding the exact card im looking for too, I guess there just wasnt a long enough period of time where the standards overlapped for there to be a market for it. Also, I have some SC->LC cables, and for whatever reason the SC ends never fit properly in the GBIC.......I wound up cracking the casing on one in the middle of the day at one of my sites, took down that whole part of the building for an hour until I coukld use enough glue and tape to hold it together :D

I havent touched those things with a 3.3m pole ever since............though im sure thats a tad overdramatic ;)
 

defaultluser

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Sorry dude, GBIC has been mad obsolete by the mini version.

They don't even make USB 3 GBIC network adapter (but there are tons of those in SFP format)
 

sinisterDei

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GBIC has been mad obsolete by the mini version
GBIC is still common industry slang for a SFP module. SFP modules are commonly referred to as mini-GBICs or oftentimes simply as GBICs, even in the case where the interface speed is higher than gigabit (which is where the G in GBIC comes from).
 

defaultluser

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GBIC is still common industry slang for a SFP module. SFP modules are commonly referred to as mini-GBICs or oftentimes simply as GBICs, even in the case where the interface speed is higher than gigabit (which is where the G in GBIC comes from).
Then why pray-tell is it so impossible for the OP to find a fiber converter from full-size to mini

He mentions finding SfP PCI card
 
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Smoblikat

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I guess I was just taught by older guys, ive always called SFP transceivers, GBICs.
 

sinisterDei

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Then why pray-tell is it so impossible for the OP to find a fiber converter from full-size to mini

He mentions finding SfP PCI card
What he wanted is a 32-bit PCI (not PCI-E or PCI-X) card with a gigabit capable SFP port on it. That's a rare combination. He ended up purchasing a 64-bit PCI-X card, some of which are will work in a standard 32-bit PCI slot, and is going to hope for the best with it.
 

GiGaBiTe

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but I would definitely need to have the full gigabit (PCI does 133MB/s I think, gigabit should be around 125, no clue why this is so hard to find)
Conventional PCI found in most desktop motherboards of yore was indeed 133 MB/s, but this was shared bandwidth with everything else in the system. The actual throughput of a single card could be much less if the bus is saturated lot of bandwidth heavy devices like video cards or disk controllers. Further crippling speed is the fact that most cheap NICs are just PHYs and the host CPU does all of the bit banging in software. Getting a full 125 MB/s on a PCI system is a pipe dream really. On my old PCI systems with gigabit NICs, 40-80 MB/s was about as good as it got.
 

IdiotInCharge

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I guess I was just taught by older guys, ive always called SFP transceivers, GBICs.
I think it's a Cisco thing; I hear 'GBIC' mostly from folks that have only been exposed to Cisco networking gear. Conversely, I haven't seen it documented as such in quite some time.
 

Smoblikat

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Conventional PCI found in most desktop motherboards of yore was indeed 133 MB/s, but this was shared bandwidth with everything else in the system. The actual throughput of a single card could be much less if the bus is saturated lot of bandwidth heavy devices like video cards or disk controllers. Further crippling speed is the fact that most cheap NICs are just PHYs and the host CPU does all of the bit banging in software. Getting a full 125 MB/s on a PCI system is a pipe dream really. On my old PCI systems with gigabit NICs, 40-80 MB/s was about as good as it got.
Very interesting, is it typical for older motherboards to use PCI bandwidth for onboard devices (similar to how PCIe is split off and used for things other than the actual slots), or would most of the losses come from other populated PCI slots? Performance isnt the main goal for me, but I also didnt know that there were "fake" NICs similar to how there are "fake" RAID cards that just offload most of the processing to the CPU, thats somthing ill keep in mind going forward.
 

GiGaBiTe

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Very interesting, is it typical for older motherboards to use PCI bandwidth for onboard devices (similar to how PCIe is split off and used for things other than the actual slots), or would most of the losses come from other populated PCI slots?
On consumer motherboards, there was generally one PCI bus coming off the north or south bridge that was shared by basically everything, regardless if it was a device integrated on the motherboard, or in a PCI slot. In the worst case, like a 440BX chipset, the PCI bus is the main path from the northbridge to the southbridge, the southbridge being on the PCI bus itself.

blockdiag.gif

Here's the i815 chipset, you can see how busy the southbridge is. You have disk controllers with PCI slots, USB controllers, sound and LAN. All of these have to share a 266 MB/s link (hub interface) from the southbridge to the northbridge. 266 MB/s is nowhere near enough bandwidth for all of those devices to run at full speed. Bus contention was a serious problem back in the day.

Later chipsets bumped the link speed bandwidth between the NB and SB up substantially, but bus contention was still a problem if devices weren't hung off the right places in the system design. Multiple CPUs on the same chipset further exacerbated problems on the front side bus and caused bus contention issues there as well, which is one of the reasons it was eliminated over a decade ago.

Performance isnt the main goal for me, but I also didnt know that there were "fake" NICs similar to how there are "fake" RAID cards that just offload most of the processing to the CPU, thats somthing ill keep in mind going forward.
There are fake NICs, disk controllers, sound cards, modems, etc. They exist because they're cheap to manufacture and because CPUs have been powerful enough to do all of the bit banging in software drivers. There are still devices being made that have dedicated DSPs to offload the processing from the host CPU, but they're expensive and usually only seen in the enterprise market these days.
 
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