2.5Gb ethernet NIC - PCIE x1 vs. USB 3.0

Riptide

Occasional Visitor
Hi. I have a high speed (2Gb) connection and a router with a 2.5Gb LAN port. I want to utilize this but my PC's integrated NIC is only 1.0Gb. Latency sensitive apps are involved here.

It seems there are two routes to take here. Either a PCI-E 1x NIC or a USB 3.0 NIC.

Is either one preferred over the other in this scenario? Thanks
 
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Tech Junky

Very Senior Member
Card is more advisable because it won't get knocked off the side / back of the PC / laptop. A single PCIE 4 lane is also faster than USB

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I wasn't aware there were PCIE4 cards out since most run on PCIE3 even 10GE. There are even legacy PCIE2 options floating around still.

https://www.amazon.com/dp/B08KVXGT4C/?tag=snbforums-20 - $100 gives you multi-gig 1/2.5/5/10GE speeds on a single card

https://www.reddit.com/r/homelab/comments/jdx39d
 

Riptide

Occasional Visitor
No you're right. The $30 2.5Gb PCI-E option I'm looking at on Amazon is only PCIE 2.0. This should be fine though since 2.5Gb is still less bandwidth than 500MB/sec that PCIE 2.0 1x offers.

So no latency penalty for going with a USB option? PC is on the floor so being knocked off/disconnected is unlikely.

Thanks
 

Tech Junky

Very Senior Member

Riptide

Occasional Visitor
Hey thanks.

Have you ever run any latency comparison testing yourself to determine if the results are the same? For ex. a ping of your local gateway/router with the USB NIC and another test with a ethernet or integrated NIC?

EDIT: N/M, a google search revealed the answer. And that is, USB NIC will add latency. However the amount added is practically inconsequential even for latency sensitive apps. Looks like I'll be picking up one of the 2.5Gb or 5Gb adapters.

Thanks again.
 
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Tech Junky

Very Senior Member
The best ping tests are from Linux as you can get sub second results. Unless your pegging the bandwidth it shouldn't vary too much.
 

tgl

Regular Contributor
FWIW, I've got one of those UGREEN 2.5G USB-C units, and it seems to work well with a MacBook Pro. Can't say about use with Linux or Windows.
 

Tech Junky

Very Senior Member
@tgl that's good to know. Since mac's run on the same kernel premise under the hood. I look at the controllers on them too for compatibility. Both the sabrent and the card I have in my server are aquantia based options which tend to be cheaper than Intel and work better than the RTL.
 

Riptide

Occasional Visitor
I ordered the trendnet. I need the USB A option on there. Sounds ridiculous but I only have one C port and it’s on the rear of the machine and doesn’t even work because ASUS botched the design of my X570 board.
 

Tech Junky

Very Senior Member
@Riptide
Yeah, I order C devices these days and picked up a set of adapters for A / Micro / Mini to have to not get different cables or devices. Tested them and found some not to be up to par and just kept ordering different options until they all did the speed they should be able to do. Since micro/mini should only do 480mbps they're not much of an issue other than being stable / charge / data. The A adapters though max out at 10gbps and some of them didn't hit the mark. I added some A >> C adapters as well just in case I want to go in the other direction as well for a power bank or charger. For ~$20 for all of the adapters it makes life simpler w/ all C cables which are good for over 10gbps / 100W PD. I did some drive tests with my new TB4 enclosure and the C cables hit 20gbps just fine. Ideally though they should have hit 30gbps because they're sturdy but, they didn't and now I have some other cables to test that I forgot about them being rated for TB use. Could save some $$ on ordering TB specific cables if they perform well.
 

Riptide

Occasional Visitor
Thanks yah in this scenario all I'm using it for is a 2.5Gbps connection so should be easily up to that task. Going to disable the onboard ethernet on this ASUS TUF X570 and convert over to this adapter as soon as I get it. GT-AX6000 gets here on Friday and that evening I'm hoping to get it installed.

Once I have the LAN up and running then I need to go and get IP Passthrough working on this AT&T BGW320 gateway. Unbeknownst to me it was doing all the firewall and routing functions for months now and my existing router was just acting as a switch. Shows you how much I knew about my setup. Discovered this little issue yesterday doing some reading around for Plex issues with double NAT.
 

Tech Junky

Very Senior Member
Always best to assume ISP CPE devices are not bridged in passthrough mode.

Now, if it was a cable modem on the other hand they're typically just dumb devices that terminate the coax and hand off Ethernet to your PC or Router.
 

Riptide

Occasional Visitor
I was coming from a cable ISP and went to fiber. I had no idea and assumed it was the same scenario. Oops.

The BGW320 can’t be put in true bridge mode so IP passthrough is best I can do.
 

Tech Junky

Very Senior Member
May not get bridge but you probably get better upload speeds. I switched from cable to test 5G FWA and it's quirky to say the least but upload speeds are usually around 80 compared to cable at 40 on a good day. No data cap to think about either. Half the price as well. Still get downloads hitting 30MB/s which isn't as high but still alright.
 

Riptide

Occasional Visitor
Got the adapter and thought I had a problem at first. 2.5Gb negotiated speeds per the NIC in windows but in reality throughput was not anywhere close to that. Turns out you need to pay attention to the orientation of the two arrows when you hook up the USB-A adapter to the USB-C connector on the NIC. It was probably noted in the documentation but who even reads that stuff am I right? :p

That immediately brought throughput to 1.2Gb per speedtest.net and is actually in excess of what I'm paying for right now which is 1000/1000.

AT&T coming out today to bump me up to 2Gb. Doubling bandwidth for an additional $30 was easy to 'justify' even though I definitely don't 'need' speeds like this.
 

Tech Junky

Very Senior Member
Yeah, orientation makes a difference sometimes. I have some crap cables that do that where the logo facing up gives me 10gbps and down only 480mbps kind of thing. Those tend to get sent back to Amazon and keep working on different cables until finding the one that actually works at speed. I'm doing this right now with thunderbolt / usb4 cables. I had one I liked for uwb-10 that actually does usb-20 now that I have something to test beyond 10gbps. So far with the drive I've been using for testing this enclosure it seems capped at 1.8GB/s for writes which is disappointing because it has low use on it. Got some new SN770's showing up today that should fix that issue.

There's always a puzzle to put together from end to end to make things work at speed. USB / Ethernet / SATA / etc. it's always something standing in the way in the chain until you figure it out.
 

Riptide

Occasional Visitor
Adapter and the router (GT-AX6000) are working per expectation.

Paying for 2000/2000 and according to speedtest.net on the one computer I have a link to support this I am getting 2350/2350.

:cool:
 

Tech Junky

Very Senior Member
Sounds about right w/ overhead / overprovisioning. On cable 1gig I was getting 1200-1500 depending on the day / which VPN server I was connected to. A lot of people don't realize there's more bandwidth because they don't have more than a 1GE port connected.
 

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