Ethernet Speeds not as good as other devices.

[QwerkyPengwen]

I've done everything I can to figure this out. I am not new to networking and how things work but this one is stumping me.

Every hard lined device in my home is getting the speeds I pay for which is 150/150 but is more accurately 155/170. However, I can't seem to figure out why the speed on only one of my PC's is locked down to 100 megabits per second resulting in my speeds being 95/95.

every other device works fine.
I am using a proper cat5e cable and I have tried using the same cable that is on another PC that gets the 155/170 to see if it was an issue with the cable and it's not.

I have made sure that drivers for LAN are properly installed and updated.

The PC in question is running Windows 10 Pro x64 and the motherboard is an AsRock Z75 Pro3 which is supposed to have a gigabit Ethernet switch but I am getting speeds that make it seem like it's a 10/100 switch.

The BIOS is the latest version as well.

Hopefully someone out there may know something that I'm missing.
If you need any additional info just ask.

This is a speedtest on the PC in question


and this is a speedtest on my other PC


I also get the faster speed on an older laptop, my PS4 and a couple of smartphones.

 

[bill001g]

Those test results pretty much prove the port is running at 100mbit. You should be able to see the speed it negotiated on. It varies just a bit depending on the version of windows but it is in the properties screen.

This is a pretty simplistic system so you only have 3 things. The ports on either end or the cable. Likely you can not set the port speed in your router., the PC you need to have it set to auto. If you set the PC side to anything other than auto and leave the router on auto the auto on the router gets confused and defaults to 100m....many times in half duplex. Other than that it has to be the cable. Cables can be just slightly defective (the connectors are just slightly loose) and they will work on some machines and not on others. All you can do is try a new cable.

There is not much else to do. If you have a port that is actual defective there is not much you can do to fix it. The speed negotiation is actually a hardware function of the chip it is not some driver you can load on most devices.

 

[QwerkyPengwen]

Those test results pretty much prove the port is running at 100mbit. You should be able to see the speed it negotiated on. It varies just a bit depending on the version of windows but it is in the properties screen.

This is a pretty simplistic system so you only have 3 things. The ports on either end or the cable. Likely you can not set the port speed in your router., the PC you need to have it set to auto. If you set the PC side to anything other than auto and leave the router on auto the auto on the router gets confused and defaults to 100m....many times in half duplex. Other than that it has to be the cable. Cables can be just slightly defective (the connectors are just slightly loose) and they will work on some machines and not on others. All you can do is try a new cable.

There is not much else to do. If you have a port that is actual defective there is not much you can do to fix it. The speed negotiation is actually a hardware function of the chip it is not some driver you can load on most devices.

As I stated in my post I used the cable that was on the other PC to see if it was the cable and it still got the same speeds.

As for port speed controls my router has that and all of my LAN ports on the router are set to 1000 Full Duplex.
So it's not the cable or the port on the router.

I am not aware of LAN port settings in windows that changes the Duplex of it. Where do I find that?


--EDIT--
Did some digging into the configure option and found it. I switched it to Gigabit Full Duplex and still no improvement. I will restart my PC to see if that helps.

 

[QwerkyPengwen]

Restarting didn't help. It's really weird. I look at the specs for this motherboard and it doesn't say anything detailed about the built in LAN port other than it's an RJ-45 port and the other thing it says about LAN is that it supports XFast LAN. But then there is a spec detail that says something about Gigabit LAN but it's simply stating that it supports PCIe x1 Gigabit Ethernet. Does the fact that they feel like they need to promote that it supports Gigabit Ethernet through PCIe mean that the on-board LAN is only 10/100 capable?

 

[bill001g]

xfast lan is some marketing gimmick mostly. It would be extremely rare to find a motherboard that did not have gigabit. All the chipsets used for many years support gigabit.

You are left with little option though. Just because it runs at gig on one machine and not on another does not mean the cable is not still bad. Some machine tolerate bad cables better than others. I would still try a new cable mostly because there is not much else you can do. You would have to use separate card there is no way to actually fix a motherboard port.

 

[QwerkyPengwen]

Again, as I have already stated. I used different cables in all ports. No luck.
But whatever. This is only my main machine that I game on.
I am fine with the 95 megabit download.
If this was happening on my dedicated stream box then I would be a little more peeved.

It's most likely the port on the motherboard that's bad.

Thanks for your time.