Pci or pcie x16 for network card

[openjacob.brown86]

The Ethernet on my system board stopped working and I have two networking cards to choose from. One is pcie and the other pci. The issue is my graphics cards cooling system covers the pcie x1 slot, so I would have to use the pcie x16 slot instead. But I also have a pci slot. So the question is if pci would slow down the Ethernet connection to much or would the pcie x16 used in this way just be a waste.

 

[Vic 40]

Which motherboard do you use?

Thought of usb adapter?

 

[openjacob.brown86]

Is usb better than an international card? I imagine not. Also I’m running Linux... so sometimes usb drivers don’t work without recompiling the kernel or using a wrapper.

 

[BFG-9000]

I would use a PCI card simply because what else are you going to use on PCI? It's going to have the bus to itself and using the other PCIe x16 slot may drop your primary x16 down to x8.

While 32-bit/33MHz PCI bus has a maximum theoretical throughput of 133MB/s so PCI gigabit cards can transfer full speed only in one direction at a time (half-duplex), when are you going to upload and download @ 1Gbit at the same time?

Intel PCI cards using the kernel-supported e1000 driver should have the least problems and just work in any distro.

The alternative is a x1 extender cable so you can mount the PCIe card somewhere else. Without working USB 3.0 drivers, USB 2.0 speeds are ~1/3 as fast as PCI and use CPU cycles to operate.

 

[openjacob.brown86]

I actually have both a pci card and a pcie card from some older systems. Based on what you are saying, pci will be faster considering that the pcie x16 is sharing the bus with the graphics card.

That said, before the built in Ethernet broke, I used full duplex to upload a video stream of primarily online games... So I’d rather not loose speed if I can help it.

As for an extender cable, I don’t know if I can fit one in the roughly one centimeter height above the slot.

I wish I could get a card made for the x16 slot, maybe a multipurpose card of some type.

 

[BFG-9000]

Using the x16 may slow down the other x16, but the PCIe NIC itself should be faster. If you are OK with your graphics card running at x8, then you could just move the GPU into the other x16 slot and then plug the NIC into the x1. Most of the extension cables do look to be right around 1cm.

Full-duplex means uploading and downloading at the same time, so for Gbit is generally only something you can saturate on the local network. Just uploading is half-duplex so cannot exceed 1Gbit of total throughput (which the PCI bus has enough bandwidth to fully supply) and no game is going to approach anywhere near that kind of download bandwidth. Over the internet would require 1000/1000 service from your ISP and direct connection to the modem or using a PC as a router, as while Smallnetbuilder has tested many routers that can move WAN-to-LAN or LAN-to-WAN at ~940Mbps, none can do both at the same time. They just don't have enough CPU.

If you are moving that kind of data, then it's probably more important to get a NIC that can offload as much of the work as possible to itself rather than having the CPU do the work (as it can take up to 2GHz of a single core just to do this) so a discrete card can be a substantial upgrade over the onboard. While there's no such thing as an IP header checksum at all in iPv6 (that can only be offloaded in iPv4), TCP and UDP pseudo-headers are payload data in iPv6 for which checksums must be calculated--it's no longer optional for UDP due to the lack of an IP header checksum. Multi-port Intel cards can also offload IPsec AH and ESP used for VPNs.

Not even 10 Gigabit ethernet cards need more than x4. And many people have found when using RAID cards that CPU-connected PCIe lanes often only work with GPUs so that x1 card may not even work in the other x16 slot. Some boards do have 3rd or 4th x16 slots that are attached to the chipset and only wired x4 (at least the CPU to chipset connection is only equivalent to x4)--those should work.

 

[openjacob.brown86]

I maybe should have mentioned that the graphics card is on one pcie x16 and the other pcie x16 is labeled pciex16_s1, so I think it runs at 4x speed even though it would be compatible with x16 cards... I’m guessing not the graphics card.

So it looks like I’ll need an extension. Thank you.