F5F Stay Refreshed Power Users Networks Why does my internet cable only give me 100 megabits per second instead of more speed?

Why does my internet cable only give me 100 megabits per second instead of more speed?

Why does my internet cable only give me 100 megabits per second instead of more speed?

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228
07-18-2026, 10:24 PM
#1
I keep searching online for advice about going into Device Manager to tweak my LAN driver speed or duplex settings, hoping to get me from auto down to a fixed 1000 Mbps setting. Right now it's set to Auto and the maximum I can see is actually 100 Mbps, so that change won't help anyway. My computer has Windows 10 on a motherboard labeled Z270X-Gaming K5.
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EliteChicagoan
07-18-2026, 10:24 PM #1

I keep searching online for advice about going into Device Manager to tweak my LAN driver speed or duplex settings, hoping to get me from auto down to a fixed 1000 Mbps setting. Right now it's set to Auto and the maximum I can see is actually 100 Mbps, so that change won't help anyway. My computer has Windows 10 on a motherboard labeled Z270X-Gaming K5.

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xoxo_blonde
Member
159
07-27-2026, 01:06 PM
#2
99 times out of 100 it is just a cable issue. Get a brand new factory-made Cat5e or Cat6a 100% copper round wire, plug it straight into your router. Your motherboard has a powerful network card. Just make sure you install the newest driver and delete all the other junk software that's slowing things down.
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xoxo_blonde
07-27-2026, 01:06 PM #2

99 times out of 100 it is just a cable issue. Get a brand new factory-made Cat5e or Cat6a 100% copper round wire, plug it straight into your router. Your motherboard has a powerful network card. Just make sure you install the newest driver and delete all the other junk software that's slowing things down.

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TheGoonDude
Junior Member
40
08-15-2026, 05:41 AM
#3
I really dislike advice about network speeds and driver settings. Usually, it's just a waste of time unless you are actually doing something with those things. Turn negotiation back on auto. But if that doesn't work, then there might be another problem entirely. Sometimes, having issues with 2.5Gbe while using gigabit routers can cause problems. In that specific case, changing the speed might help. Your real issue is probably your cables or router/switches. If you have used a switch to connect things together and those are gigabit devices, then it's likely just the cable. There isn't really anything called cat 7 or higher; if you had one of those, they would be fake according to my experience. You should use standard cat 5e or cat 6 cables for normal tasks. For gigabit speeds to work properly, all eight wires need to be in good shape. If one wire is faulty, the speed drops down to megabit because only four wires are needed then.
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TheGoonDude
08-15-2026, 05:41 AM #3

I really dislike advice about network speeds and driver settings. Usually, it's just a waste of time unless you are actually doing something with those things. Turn negotiation back on auto. But if that doesn't work, then there might be another problem entirely. Sometimes, having issues with 2.5Gbe while using gigabit routers can cause problems. In that specific case, changing the speed might help. Your real issue is probably your cables or router/switches. If you have used a switch to connect things together and those are gigabit devices, then it's likely just the cable. There isn't really anything called cat 7 or higher; if you had one of those, they would be fake according to my experience. You should use standard cat 5e or cat 6 cables for normal tasks. For gigabit speeds to work properly, all eight wires need to be in good shape. If one wire is faulty, the speed drops down to megabit because only four wires are needed then.

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Aaron_Hussain
Junior Member
7
08-16-2026, 05:01 PM
#4
I guess this could be my router stopping the internet. I ordered the cable from Walmart and they promised gigabit speeds, so I don't think it's fake.
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Aaron_Hussain
08-16-2026, 05:01 PM #4

I guess this could be my router stopping the internet. I ordered the cable from Walmart and they promised gigabit speeds, so I don't think it's fake.

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juanpiraigosa
Junior Member
26
08-17-2026, 03:21 AM
#5
LAN speeds usually need to match the internet speed you buy from the ISP, so make sure your router shows that same speed. Even if your internet is slow, check the settings and it should show the right number.
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juanpiraigosa
08-17-2026, 03:21 AM #5

LAN speeds usually need to match the internet speed you buy from the ISP, so make sure your router shows that same speed. Even if your internet is slow, check the settings and it should show the right number.

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FinnGore
Member
60
08-17-2026, 05:11 AM
#6
It might happen if either end or both ends of the cable aren't crimped right. I've had this problem before too. When I bought some cables, a few weren't crimped properly at all. Just using megabit instead of gigabit. I fixed it with a crimping tool. If you know someone who has a crimping tool for RJ45 plugs, try them out. All that is needed is to push the contact blades through the wires so one end couldn't have made it all the way through. Just press down on the crimp and that's enough.
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FinnGore
08-17-2026, 05:11 AM #6

It might happen if either end or both ends of the cable aren't crimped right. I've had this problem before too. When I bought some cables, a few weren't crimped properly at all. Just using megabit instead of gigabit. I fixed it with a crimping tool. If you know someone who has a crimping tool for RJ45 plugs, try them out. All that is needed is to push the contact blades through the wires so one end couldn't have made it all the way through. Just press down on the crimp and that's enough.

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Xeitizen
Junior Member
8
08-19-2026, 01:53 PM
#7
bro I just changed the internet cable to a different one on the router, and now there is no speed limit!
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Xeitizen
08-19-2026, 01:53 PM #7

bro I just changed the internet cable to a different one on the router, and now there is no speed limit!

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PersieO
Posting Freak
786
08-20-2026, 08:42 AM
#8
So cable works okay and I'm happy. Try using the other plug when you can. Maybe give it a good shake to pop it loose. It should work, just not perfectly tight. If you like me, be cool! 👍
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PersieO
08-20-2026, 08:42 AM #8

So cable works okay and I'm happy. Try using the other plug when you can. Maybe give it a good shake to pop it loose. It should work, just not perfectly tight. If you like me, be cool! 👍