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