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rado3105
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rb44ge is ok to use it in pci-E 1x,

Sat Mar 26, 2016 11:55 pm

Today I starte to use rb44ge 4x pcie ethernet card in jnc9t with PCIE 1x. I am using just 2 ports, another 2 ports I disabled. Should I expect any problems? thanks
 
IntrusDave
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Re: rb44ge is ok to use it in pci-E 1x,

Sun Mar 27, 2016 1:04 am

if it physically fits in the slot, it will work. It's common to find boards with x1, x4 and x8 in a larger slot. The PCIe protocol will detect what is available and use it. However, if the board doesn't fit in the slot, don't force it.
 
rado3105
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Re: rb44ge is ok to use it in pci-E 1x,

Sun Mar 27, 2016 1:19 am

I fitted 4x card in 1x slot...just cut the end of the pcie....
 
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chechito
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Re: rb44ge is ok to use it in pci-E 1x,

Sun Mar 27, 2016 5:54 am

rb44ge is pci exp 2.0, in theory with one lane of pci express 2.0 you have 4gbit of bandwidth, thats just enough for 2 gigabit ports in full duplex operation

looking the photo of that card it has a pex 8606 bridge that bridge is only 6 internal lanes of pci express, that means the card uses 4 lane of that internal switch for the 4 atheros gigagit ethernet controllers and leaves only 2 lanes for connection to host, in conclusion that card uses only 2 lanes of pci express on motherboard slot
 
rado3105
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Re: rb44ge is ok to use it in pci-E 1x,

Sun Mar 27, 2016 9:30 am

according to that, it should be ok...
 
Quindor
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Re: rb44ge is ok to use it in pci-E 1x,

Mon Mar 28, 2016 3:08 am

rb44ge is pci exp 2.0, in theory with one lane of pci express 2.0 you have 4gbit of bandwidth, thats just enough for 2 gigabit ports in full duplex operation

looking the photo of that card it has a pex 8606 bridge that bridge is only 6 internal lanes of pci express, that means the card uses 4 lane of that internal switch for the 4 atheros gigagit ethernet controllers and leaves only 2 lanes for connection to host, in conclusion that card uses only 2 lanes of pci express on motherboard slot
Just a quick correction, PCIe is always full-duplex meaning that PCIe 2.0 x1 provides you with 4Gbps full-duplex (So 4 up and down at the same time).

So PCIe 2.0 x1 should indeed be enough to be able to saturate all 4 ports at full-duplex Gigabit speeds.
 
IntrusDave
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Re: rb44ge is ok to use it in pci-E 1x,

Mon Mar 28, 2016 3:34 am

The only issue I have with this is the physical connection. PCIe connections are very small and need to be securely in the slot. Cutting an x1 slot to fit a larger card isn't a great idea. Misalignment can end in disaster.

You will also need to make sure that the interfaces can indeed share the same lane. Some multi port cards use independent lanes, where a x1 port will only activate a single interface.
 
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chechito
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Re: rb44ge is ok to use it in pci-E 1x,

Mon Mar 28, 2016 7:24 am

The only issue I have with this is the physical connection. PCIe connections are very small and need to be securely in the slot. Cutting an x1 slot to fit a larger card isn't a great idea. Misalignment can end in disaster.

You will also need to make sure that the interfaces can indeed share the same lane. Some multi port cards use independent lanes, where a x1 port will only activate a single interface.

you have reason, i suppose the cut on the pci express motherboard slot is like this
pcie-carved-1.jpg
to avoid the misalignment problem

i think in the case of this card the PLX pci express switch allow the sharing of pci express lanes by the 4 atheros gigabit ethernet ports

quindor clarification leaves all clear about bandwidth
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rado3105
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Re: rb44ge is ok to use it in pci-E 1x,

Tue Mar 29, 2016 7:10 pm

In comparison with integrated realteks I have worse latency, can be that because of this pcie?
 
mpreissner
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Re: rb44ge is ok to use it in pci-E 1x,

Wed Mar 30, 2016 8:27 pm

Just a quick correction, PCIe is always full-duplex meaning that PCIe 2.0 x1 provides you with 4Gbps full-duplex (So 4 up and down at the same time).

So PCIe 2.0 x1 should indeed be enough to be able to saturate all 4 ports at full-duplex Gigabit speeds.
Quindor is exactly right. PCIe bandwidth is usually rated in Megabytes per second, and PCIe 2.0 runs at 500MB/sec per lane in both directions (full-duplex). Multiply by 8 to convert from bytes to bits, and you get 500MB x 8 = 4gbps per lane full duplex. So yes, a PCIe 2.0 quad port gigabit card can reach full saturation in an x1 slot, but you're right up against the PCIe bandwidth limit.
 
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chechito
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Re: rb44ge is ok to use it in pci-E 1x,

Wed Mar 30, 2016 10:05 pm

In comparison with integrated realteks I have worse latency, can be that because of this pcie?
how much difference in latency?? the high latency is with interfaces maxed out at full duplex or without traffic??

avago promotes pex switches as low latency of 190ns
http://www.avagotech.com/products/pcie- ... ifications

are you using rb44ge with ROUTER OS or another OS??
 
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Re: rb44ge is ok to use it in pci-E 1x,

Sun Oct 22, 2017 6:22 pm

Isso use 250 minning expert. Support 19 VGA cards, but not support more than 3 NIC rb44ge. Why?
 
rado3105
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Re: rb44ge is ok to use it in pci-E 1x,

Wed Jan 24, 2018 1:09 pm

I started to have problem with rb44ge during high load, about 300Mbit/s and 20 000pps. Does anybody know how much pps can go through rb44ge?

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