How to double the speeds with two Ethernet cables?

[Razzee]

I have each one of those cards now installed in a different motherboard:

 

1. Gigabyte GA-B75M-D3H (Rev. 1.0);

2. Gigabyte GA-Z68XP-UD3 (Rev. 1.3).

 

Although the Ethernet cards are the only component occupying the PCI slot, the speeds did not improve!

 

Are the speeds limited per slot even if I don't use both at the same time?

 

Sucks...

 

https://i.imgur.com/R3nsuJf.png

[Blue4130]

2 hours ago, Razzee said:

I have each one of those cards now installed in a different motherboard:

 

1. Gigabyte GA-B75M-D3H (Rev. 1.0);

2. Gigabyte GA-Z68XP-UD3 (Rev. 1.3).

 

Although the Ethernet cards are the only component occupying the PCI slot, the speeds did not improve!

 

Are the speeds limited per slot even if I don't use both at the same time?

 

Sucks...

 

https://i.imgur.com/R3nsuJf.png

You didn't answer my question. What harddrive or ssd are you using? You could very well be speed limited if you are using some old sata harddrive.

[Razzee]

13 hours ago, Blue4130 said:

You didn't answer my question. What harddrive or ssd are you using? You could very well be speed limited if you are using some old sata harddrive.

 

This is not even relevant, since I'm running SpeedTest.

 

In any case, the operating system is installed on a SATA SSD (Hikvision C100 480 GB).

 

Since the speeds have not improved at all, I will use both PCI slots again.

[Alex Atkin UK]

3 hours ago, Razzee said:

 

This is not even relevant, since I'm running SpeedTest.

 

In any case, the operating system is installed on a SATA SSD (Hikvision C100 480 GB).

 

Since the speeds have not improved at all, I will use both PCI slots again.

I thought the problem was the LAN to LAN speed?  This is where even your CPU will be relevant and definitely the storage in each of the PCs you are copying between.

[Razzee]

19 minutes ago, Alex Atkin UK said:

I thought the problem was the LAN to LAN speed?  This is where even your CPU will be relevant and definitely the storage in each of the PCs you are copying between.

 

The problem is... both.

 

The download speeds on the system as well as transfer speeds, both are being limited for some reason.

 

I'm constantly transfering MP4 videos (gameplay) between PCs, so I leave only one uploading to YouTube at night.

 

The download speeds (SpeedTest) you already know. This is the max speed between PCs:

 

 

From a Lexar NM620 1 TB (i7-3770) to a Hikvision C100 480 GB (i5-3570), through the PCI Gigabit Ethernet adapter.

 

64 MB/s is roughly 512 Mbps, exactly half of 1024 Mbps. It should be transferring at 128 MB/s.

 

The speeds are the same, regardless if both PCI slots are populated or not. 

[mynameisjuan]

12 hours ago, Razzee said:

This is not even relevant, since I'm running SpeedTest.

It's actually relevant and almost always overlooked. Most speed tests utilize disk depending on memory and throughput and write performance can actually impact the results along with other factors such as CPU. It's essentially downloading many files of random data and cached until completed. Look at task manager when running a test and you'll see.

 

If you want to remove as many variables as possible limiting to the CPU/memory/NIC and throughput, try again with iPerf3 between the PCs as it runs in memory and will give you more realistic results of network performance.

[Razzee]

On 11/13/2023 at 9:22 PM, mynameisjuan said:

It's actually relevant and almost always overlooked. Most speed tests utilize disk depending on memory and throughput and write performance can actually impact the results along with other factors such as CPU. It's essentially downloading many files of random data and cached until completed. Look at task manager when running a test and you'll see.

 

If you want to remove as many variables as possible limiting to the CPU/memory/NIC and throughput, try again with iPerf3 between the PCs as it runs in memory and will give you more realistic results of network performance.

 

As I said several times, it has nothing to do with that.

 

These are the speeds with a PCI-E 2.5 Gbps Ethernet adapter:

 

 

 

However, I need to use both PCI-E slots for another component, which is not an Ethernet card.

[Alex Atkin UK]

14 minutes ago, Razzee said:

 

As I said several times, it has nothing to do with that.

 

These are the speeds with a PCI-E 2.5 Gbps Ethernet adapter:

 

 

 

However, I need to use both PCI-E slots for another component, which is not an Ethernet card.

Then you've proven what was already discussed, this is a limitation of the PCI bus, everything on it shares the same bandwidth and the speed claimed is before overheads so it can never reach Gigabit.

Get a USB 3.0 adapter, its what I have on my Mac Mini and ITX PC.

[mariushm]

On 11/12/2023 at 9:27 PM, Razzee said:

I have each one of those cards now installed in a different motherboard:

 

1. Gigabyte GA-B75M-D3H (Rev. 1.0);

2. Gigabyte GA-Z68XP-UD3 (Rev. 1.3).

 

Although the Ethernet cards are the only component occupying the PCI slot, the speeds did not improve!

 

Are the speeds limited per slot even if I don't use both at the same time?

 

Sucks...

 

https://i.imgur.com/R3nsuJf.png

 

PCI bus is limited to 133 MB/s 

 

Your ethernet card is 1 gbps  or 1,000,000,000 bits per second. There's 8 bits in a byte, so a maximum of 125 MB/s, because you divide using 1000 to get KB, then you divide by 1000 to get MB.

 

So that's the maximum theoretical speed of your 1 gbps ethernet card, if there's no other device sharing the PCI bus you can achieve maximum speed because the bus can do 133 MB/s.

 

Data you transfer or download, pretty much anything, is arranged in packets, when you download something that stuff doesn't come as a stream of bytes, it comes as packets of data, each packet with a small header. 

 

Keeping it super simple, just assume that out of those 125 MB/s, around 2-4 MB/s will be used by packet information, overhead, so the actual usable transfer will be 120-122 MB/s 

 

Windows uses multiples of 1024 when showing file sizes, and lots of other things. It's for historical reasons, for backwards compatibility and for lots of other reasons that have to do with math and optimizations. It's just easier to divide by multiples of 2 (1024 = 2¹⁰) 

 

That 109 MB/s  in the picture may very well be 109 x 1024 x 1024 = 114,294,784  bytes  or 114.2 MB/s  ... which is quite close to 120-122 MB/s that's the maximum possible. 

 

 

[Razzee]

1 hour ago, Alex Atkin UK said:

Then you've proven what was already discussed, this is a limitation of the PCI bus, everything on it shares the same bandwidth and the speed claimed is before overheads so it can never reach Gigabit.

Get a USB 3.0 adapter, its what I have on my Mac Mini and ITX PC.

 

I'll look into that.

 

But why would they make Gigabit Ethernet controllers using PCI slots?

 

I imagine that many customers would complain a lot about the speeds, mostly people who keep a server running.

 

Perhaps a motherboard with a single PCI slot, such as the Gigabyte GA-B75M-D3P, does not limit the speeds.

[Alex Atkin UK]

2 minutes ago, Razzee said:

 

I'll look into that.

 

But why would they make Gigabit Ethernet controllers using PCI slots?

 

I imagine that many customers would complain a lot about the speeds, mostly people who keep a server running.

 

Perhaps a motherboard with a single PCI slot, such as the Gigabyte GA-B75M-D3P, does not limit the speeds.

Because its the only way to get more than 100Mbit.  The same reason there are Gigabit USB 2.0 adapters and 5Gbit USB 3.0 Gen 1 adapters.

 

A single PCI slot likely wont make a difference, you're running into protocol overheads of the PCI bus even on a single card.

[Razzee]

Changing a bit the subject, I managed to connect two computers via Crossover cable.

 

PC1: Realtek RTL8125B

PC2: Intel I-225V

 

Transfer speed via Network (1 Gbps):

 

 

105 MB/s * 8 = 840 Mbps

 

Transferring via Crossover cable (2.5 Gbps):

 

 

159 MB/s * 8 = 1272 Mbps

 

While I think it is working, since it broke the barrier of Gigabit, I wish it could go further than that...

[AbydosOne]

3 minutes ago, Razzee said:

I managed to connect two computers via Crossover cable

Crossovers aren't necessary with anything faster than 100Mbps Ethernet. The NICs will negotiate Tx/Rx pairs automatically.

[Razzee]

44 minutes ago, AbydosOne said:

Crossovers aren't necessary with anything faster than 100Mbps Ethernet. The NICs will negotiate Tx/Rx pairs automatically.

 

The domestic standard today is still 1 Gbps, so my switches and router are 1 Gbps-compliant. 

 

I found these three 2.5 Gbps Ethernet cards at Shopee, but to make use of them I had to connect my computers directly.

 

I said "Crossover", but it's not like I did anything out of ordinary. I just used a normal cable and set a fixed IP for each Ethernet adapter.

 

Both folders have their own shortcut (Crossover and Network):

 

 

The issue is that I can connect PC1 to PC2, but PC2 is unable to access PC1. I don't know why. It says the folder is invalid.

 

PC1 is using Windows 11, PC2 has Windows 10.

[AbydosOne]

28 minutes ago, Razzee said:

The issue is that I can connect PC1 to PC2, but PC2 is unable to access PC1. I don't know why. It says the folder is invalid.

Did you set the IPs of the 2.5G NICs to a different subnet from the 1G NICs?

[Razzee]

32 minutes ago, AbydosOne said:

Did you set the IPs of the 2.5G NICs to a different subnet from the 1G NICs?

 

Certainly. One ends with 17, the other 18. 

 

I made sure that no other device in the network uses the same IP.

[AbydosOne]

32 minutes ago, Razzee said:

 

Certainly. One ends with 17, the other 18. 

 

I made sure that no other device in the network uses the same IP.

Different subnet. Not different IPs.

 

If your primary network is 192.168.1.x, your direct connection IPs need to be 192.168.2.x (or any number other than 1 in place of the 2; this assumes your subnet mask is the default 255.255.255.0). Otherwise Windows asks the router where that IP is, and the router doesn't know because that IP isn't connected to it, and the connection fails. Also, leave the gateway blank in the config as well (for much the same reason; in a direct connection, there is no gateway).

[Alex Atkin UK]

8 hours ago, Razzee said:

Transferring via Crossover cable (2.5 Gbps):

 

 

159 MB/s * 8 = 1272 Mbps

 

While I think it is working, since it broke the barrier of Gigabit, I wish it could go further than that...

It can do more than that, if both ends can handle it.

 

From a HDD:

 

From a SSD:

 

But it can get very CPU heavy, that's between an i5 12400F and a Ryzen 9 5950X.

[Razzee]

On 11/15/2023 at 8:14 PM, AbydosOne said:

Different subnet. Not different IPs.

 

If your primary network is 192.168.1.x, your direct connection IPs need to be 192.168.2.x (or any number other than 1 in place of the 2; this assumes your subnet mask is the default 255.255.255.0). Otherwise Windows asks the router where that IP is, and the router doesn't know because that IP isn't connected to it, and the connection fails. Also, leave the gateway blank in the config as well (for much the same reason; in a direct connection, there is no gateway).

 

PC1 (Windows 11):

 

 

PC2 (Windows 10:

 

 

PC1 can access PC2, PC2 cannot access PC1 at all (via Network or Crossover).

 

It simply says that "O Windows não pode localizar \\192.168.0.17. Verifique a ortografia e tente novamente".

 

"Windows cannot locate (IP or PC name)" Check the ortography and try again."

 

If I type the name of the PC (Zweitestock), it cannot be found either. I have set all permissions (folder) to "Everyone".

 

Also:

 

[Alex Atkin UK]

3 hours ago, Razzee said:

PC1 can access PC2, PC2 cannot access PC1 at all (via Network or Crossover).

 

It simply says that "O Windows não pode localizar \\192.168.0.17. Verifique a ortografia e tente novamente".

 

"Windows cannot locate (IP or PC name)" Check the ortography and try again."

 

If I type the name of the PC (Zweitestock), it cannot be found either. I have set all permissions (folder) to "Everyone".

Probably unrelated, but don't set a gateway on a network that doesn't HAVE a gateway (router) such as when using a cable between two PCs.

 

Make sure on PC1 the firewall is set to Private or turned off for that network, that's usual reason for not being able to connect to it.

[Razzee]

12 minutes ago, Alex Atkin UK said:

Probably unrelated, but don't set a gateway on a network that doesn't HAVE a gateway (router) such as when using a cable between two PCs.

 

Make sure on PC1 the firewall is set to Private or turned off for that network, that's usual reason for being able to connect to it.

 

It was the firewall (Kaspersky's).

 

 

Thank you kindly.