[SOLVED] Ethernet connection slows from 400mbps to 100mbps within a few minutes ?

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Parroty69

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My ethernet has 400mbps immediately after plugging and the adapter status for Realtek PCIe Family Controller shows that it has 1 gigabit:
View: https://imgur.com/cGKpHrP

But after a few minutes it slows down to 100mbps in a speedtest and the adapter status says the speed is 100mbps:
View: https://imgur.com/gDpnIuV

I used multiple cables to test it but a cat6 stays at 100mbps the whole time. And a crappy broken cat5e cable that i had lying around (the one that is in the pictures) begins at 400mbps and slows down to 100mbps like I said
Both cables are UTP cables and the cat6 one is a flat cable. Cat 5e cable is round
I think this is a cable issue because trying out different cables give different results. Do you have any suggestions to fix this issue?
 
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Solution
Sounds like you have 2 bad cables. The cat5e sounds like it was somehow damaged or is just very old.

The cat6 cable you have is a fake cable. Flat cables have wires that are too thin to meet the specification of ethernet. Because the wire is none conforming you can get all kinds of strange errors.

Buy a cat5e or cat6 cable that is pure copper with wire size 22-24
Does the 50 micron gold and the 100 microinch nickel do anything?
Why did you choose to use upgrade your house to 10gig when you only have 1.2gig, is it to futureproof it?

The gold and nickel plating won't really help bandwidth much, but will help prevent corrosion so it'll help maintain speed and make the cable more reliable long term.

I didn't upgrade to 10gbe for my internet. Instead I needed the speed to move data between my computers, my server and my NAS inside the house.
 

Parroty69

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The gold and nickel plating won't really help bandwidth much, but will help prevent corrosion so it'll help maintain speed and make the cable more reliable long term.

I didn't upgrade to 10gbe for my internet. Instead I needed the speed to move data between my computers, my server and my NAS inside the house.
What were the read and write speeds? I suppose those are also affected by the speed of the disks on your server and NAS.
Does TIA/EIA-568-B.2-1 mean anything?
 
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Most times you see TIA/EIA markings on quality ethernet cables. They have to pay for the rights to print that on their cable. It generally means the company has shown it makes cables that meet the certification for ethenet. EIA/TIA is one of the 3 or so core specifications used for ethernet.

BUT we have companies in china that make fake purses etc that will print those markings without the actual license to do it. You can't 100% trust it any more.

568-b is is one of the two common options on how the wires are arranged on the ends. If you were to look the left most wires on the plug will be orange/white and orange. It really doesn't matter much. They used to make cable with 568-a on one end and 568-b on the other. This was years ago when you needed crossover cables.
 

Parroty69

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Most times you see TIA/EIA markings on quality ethernet cables. They have to pay for the rights to print that on their cable. It generally means the company has shown it makes cables that meet the certification for ethenet. EIA/TIA is one of the 3 or so core specifications used for ethernet.

BUT we have companies in china that make fake purses etc that will print those markings without the actual license to do it. You can't 100% trust it any more.

568-b is is one of the two common options on how the wires are arranged on the ends. If you were to look the left most wires on the plug will be orange/white and orange. It really doesn't matter much. They used to make cable with 568-a on one end and 568-b on the other. This was years ago when you needed crossover cables.
I'm buying directly from the manufacturer so there might be less of a chance that the marking is fake.
How can I know that the ETA/TIA on my cable is real?
What are the other two specifications and how do I know they're real?
 
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You never know which is why you buy from company you can trust. In some ways buying from a local company where you can take it back and complain.

It is not common for companies to outright lie. Amazon has a least forced companies that sell CCA cable to put that in there listing.

So if the company says the wire is pure copper and has a certain wire size those tend to be honest. What companies that are being deceptive do is either not provide that information or they do provide it and assume the consumer is too lazy to look up what CCA means and know that is a invalid metal. You average consumer is more interest in the cost and saving 2 pennies

In some ways it would be nice if it were illegal to sell cable that did not meet the standard like the do with electrical power cables. Then again you can get shady power cables if you buy from one of the sites that ship directly out of china.
 

Parroty69

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You never know which is why you buy from company you can trust. In some ways buying from a local company where you can take it back and complain.

It is not common for companies to outright lie. Amazon has a least forced companies that sell CCA cable to put that in there listing.

So if the company says the wire is pure copper and has a certain wire size those tend to be honest. What companies that are being deceptive do is either not provide that information or they do provide it and assume the consumer is too lazy to look up what CCA means and know that is a invalid metal. You average consumer is more interest in the cost and saving 2 pennies

In some ways it would be nice if it were illegal to sell cable that did not meet the standard like the do with electrical power cables. Then again you can get shady power cables if you buy from one of the sites that ship directly out of china.
I have used cables from that company before (it is the company that made cat5e cable that is broken but can reach speeds of 440mbps). So I think it might be safe.
What do you think?
 
Any cable can break. It all depends exactly what happened. It can not work at all, maybe only run 100mbps or in some cases it just takes a lot of errors which reduces your speed.

When you look at how data is being transferred your to called 440mbps cable is actually running at 1gbit. A ethernet port either runs a full speed or runs at zero. Not real useful numbers though because you would only see 1gbit and zero no matter how much usage you have. So data rates are average rates over a number of seconds. These rates can be affected by many things. In this case we are talking about data loss in the ethernet but it can also be affected by issues with the application program or if you testing to the internet some restriction in the paths in the internet.
 

Parroty69

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Any cable can break. It all depends exactly what happened. It can not work at all, maybe only run 100mbps or in some cases it just takes a lot of errors which reduces your speed.

When you look at how data is being transferred your to called 440mbps cable is actually running at 1gbit. A ethernet port either runs a full speed or runs at zero. Not real useful numbers though because you would only see 1gbit and zero no matter how much usage you have. So data rates are average rates over a number of seconds. These rates can be affected by many things. In this case we are talking about data loss in the ethernet but it can also be affected by issues with the application program or if you testing to the internet some restriction in the paths in the internet.
The broken cat5e cable reached speeds of 440mbps (my internet plan) in a speedtest and was broken from wear and tear and it was at least 3 years old.
It seems that the cables they make are reliable cables.
 

bniknafs9

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it could be your cable , it could be the port on your modem/router , it could be your computer's lan port too .
try updating your lan's driver , like with windows update or downloading from your motherboads vendor aswell. see if that helps with speed negotiating problem that you are experiencing
 

Parroty69

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it could be your cable , it could be the port on your modem/router , it could be your computer's lan port too .
try updating your lan's driver , like with windows update or downloading from your motherboads vendor aswell. see if that helps with speed negotiating problem that you are experiencing
I have already updated the drivers by downloading from Realtek. It found like 5 driver versions and automatically installed the newest one.
 
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Parroty69

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Any cable can break. It all depends exactly what happened. It can not work at all, maybe only run 100mbps or in some cases it just takes a lot of errors which reduces your speed.

When you look at how data is being transferred your to called 440mbps cable is actually running at 1gbit. A ethernet port either runs a full speed or runs at zero. Not real useful numbers though because you would only see 1gbit and zero no matter how much usage you have. So data rates are average rates over a number of seconds. These rates can be affected by many things. In this case we are talking about data loss in the ethernet but it can also be affected by issues with the application program or if you testing to the internet some restriction in the paths in the internet.
Should I replace my broken ethernet cable if it works fine?
 
I would always have a spare ethernet cable you never know when the dog chews it or you trip over it and break it.

Maybe I got lost in this long thread. I though you said it didn't work properly. As long as the wires inside are not damaged it should be fine.

The outside jacket is mostly a second layer of protection for the wires carrying the data. It also helps keep the small wires from being pulled out of the plug. Properly made cables the outside jacket is crimped into the plug and actually takes most the stress if you pull on the cable.
 

Parroty69

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I would always have a spare ethernet cable you never know when the dog chews it or you trip over it and break it.

Maybe I got lost in this long thread. I though you said it didn't work properly. As long as the wires inside are not damaged it should be fine.

The outside jacket is mostly a second layer of protection for the wires carrying the data. It also helps keep the small wires from being pulled out of the plug. Properly made cables the outside jacket is crimped into the plug and actually takes most the stress if you pull on the cable.
The brown wire (not striped) of the cable has a broken shell an I can see the conductor material.
EDIT: The speed of the connection has dropped to 100mbps again with the cat5e cable.
View: https://imgur.com/oFYRMBO
 
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You it need all 8 wires to be good to get gigabit speeds.

100mbit only uses the green and orange pairs. If one of those are damaged the cable will just completely fail randomly.

Partially broken wires in a cable will cause it to be intermittent. Very slight changes is temperature will cause the metal to expand and contract and it may have a almost invisible break open up.

You can technically fix cables by replacing the ends or if the cable is very long and the problem is in the middle you can make it into 2 cables and use a rj45 coupler. Buying a new cable tends to be cheaper. The cost of the ends and the tool will be more and it take practice to put the ends on correctly.

So I think you are back in search of a good quality ethernet cable
 

Parroty69

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You it need all 8 wires to be good to get gigabit speeds.

100mbit only uses the green and orange pairs. If one of those are damaged the cable will just completely fail randomly.

Partially broken wires in a cable will cause it to be intermittent. Very slight changes is temperature will cause the metal to expand and contract and it may have a almost invisible break open up.

You can technically fix cables by replacing the ends or if the cable is very long and the problem is in the middle you can make it into 2 cables and use a rj45 coupler. Buying a new cable tends to be cheaper. The cost of the ends and the tool will be more and it take practice to put the ends on correctly.

So I think you are back in search of a good quality ethernet cable
So basically I need a cable with:
22-24awg
Pure copper
Round
Is at okay to have a SSTP or SFTP cable if you're only using it for connecting a PC to a router?
 

Parroty69

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It looks like you have two bad cables. Cat5 sounds like it's damaged in some way or very old. You have a cat6 cable - fake. Flat cables have wires that are too thin to meet Ethernet specifications. All sorts of weird errors can occur because the wires are out of specification. Buy a pure copper cat5e or cat6 cable with wire size 22-24.
Why did you copy bill001g's answer?
 

Parroty69

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I am planning to buy a different cable from a more reputable brand. It is a 24awg pure copper stranded 100mhz cable and it is from Commscope.
Is this cable good?
Is this brand reputable?
 

Parroty69

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commscope is a well know wire manufacture. I didn't know they made patch cables...then again maybe the company you buy from purchased bulk cable and put the ends on.
Commscope does make patch cables. The company I'm planning to buy it from says that it is produced by Commscope and it wasn't made by the company. The model of the cable is npc06uvdb-bl010f.
 
Not sure where you see 100mhz.

This is the link from commscope.

It says it supports ISO/IEC 11801 Class E. This is the technical name for cat6 cable. It will run at 250mhz. But it doesn't matter even if it were 100mhz that is what cat5e runs at.

When you start seeing details like this is how you know this is going to be quality cable. They are using the very technical descriptions rather than saying stuff like "cat6". This means they have certified the cable to meet the technical standard they list.
 

Parroty69

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Not sure where you see 100mhz.

This is the link from commscope.

It says it supports ISO/IEC 11801 Class E. This is the technical name for cat6 cable. It will run at 250mhz. But it doesn't matter even if it were 100mhz that is what cat5e runs at.

When you start seeing details like this is how you know this is going to be quality cable. They are using the very technical descriptions rather than saying stuff like "cat6". This means they have certified the cable to meet the technical standard they list.
Is this cable copper? I said it was copper but I'm not sure.
 
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