4-port NIC for PCIe 2.0 x1 slot

[epobirs]

We're looking at building some pfSense boxes small enough to go in carry-on luggage. To fulfill the requirements the finished machine needs at least four GbE ports. One board I've been looking at is the ASUS N3150I-C. This has a single PCIe 2.0 x4 slot that operates in x1 mode. The quad-port low profile NICs I've found require a PCIe x4 slot but that is under the 1.0a generation of PCIe.

A single 2.0 lane should have enough bandwidth to handle the load. Does anyone make a low profile quad-port NIC designed to work with a single PCIe 2.0 lane? It would need to be supported by BSD, of course, to be used by pfSense.

 

[drtweak]

Well it SHOULD just switch to 1x mode but I have not tested this on a Quad NIC card before. You're better off find a board with at least a 4x PCIe slot.

The thing is even though the NIC needs 4 lanes of PCIe 1.0a, putting that in a 1x 2.0 slot will NOT give you 2.0 speeds as the card it self is PCIe 1.0 specs. The card will run at what ever the lowest rating is whether it is the card or the PCIe slot.

So 1 lan of PCIe 1.0 is 250MB and if you plan on maxing out that quad port with all 4 Gigabit's you will need at least 500MB of bandwith which is why the card is a 4x (2x cards are VERY Rare) giving you 1000MB of bandwith.

Best thing is to find another board. or find a PCIe 2.0 Quad NIC Card

 

[drtweak]

Here are a few

http://www.newegg.com/Product/Product.aspx?Item=N82E16833106049

http://www.newegg.com/Product/Product.aspx?Item=N82E16833106050

They look low profile and not sure about BSD Support but they are out there.

 

[epobirs]

Both of those have low profile brackets shown in the 'all the bits in the box' photos, so they're good on that front. If they're from Intel they're almost guaranteed to have BSD support. The only downside is the price is a lot higher than the older cards but the multi-lane slot requirements of those older cards is likely why they're now being discounted heavily.

 

[epobirs]

http://ark.intel.com/products/49186/Intel-Ethernet-Server-Adapter-I340-T4

Drat. Even though a single lane of 2.0 should suffice, these models still want an x4 slot. I'll have to see if they work in the ASUS board x4 slot that operates at x1 speed.

 

[drtweak]

Yea not sure. I know Video cards will just run at whatever lanes they are given, not sure about these guys. Best bet - Contact Intel Support on it if you can.

Do you already have this motherboard or that is just what you are looking to buy?

 

[epobirs]

The only part I've committed to thus far is a pair of Antec ISK310 case and power supply units, mainly because Fry's had a special today that reduced the price by about 40% and I couldn't resist. I'll do SOMETHING with them, if not this particular project. HTPC is the leading candidate, of course.

For the pfSense application these boards are actually overkill as far as features go but the trick has been finding something to meet the goal (NOC in carry-on luggage) without going too far in the opposite direction. The need for a minimum of four GbE ports is critical. I've considered using a dual-port NIC and a USB 3.0 to GbE dongle as an alternative but we've yet to see how this behaves in pfSense.

Our older ultraportable boxes, which are getting pretty long in the tooth and verging on useless, were ATOM boards with a mezzanine riser that allowed for a couple of PCI slots, one of them with a dual-port card and the other with a single port in addition to the port on the motherboard. This was back when 100 Mb ports would serve. A similar board with a pair of 2.0 x1 slots that could take a dual-port card each would be great but we've yet to come across any. There are several brands of 'lunchbox' PCs that would take the cards but are quite expensive.

The only boards I've found that have enough native ports are the same ones already used in the pfSense appliances sold on their site, which we'd already decided against. If somebody made a current generation ATOM board with at least two network ports and a slot sufficient for a dual-port card, we'd definitely want to know.