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The Graveyard - Products No Longer Supported => Routers / COVR => DIR-655 => Topic started by: samtng on September 30, 2009, 09:25:49 AM
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Hi everyone,
I'm having problem with the Dir-655 LAN ports.
Router DIR-655 info:
updated to lastest firmware: 1.32NA
Things are connected to DIR-655:
Laptop (dv4t-1000) w/ gigabit network: showed only 100Mbps
OS: Vista Home Premium 64bit
network card: Realtek brand
There is only 10Mbps half/full duplex, 100Mbps half/full duplex, and Auto Negotiation under Configure/Advanced tab.
Any idea?
Thank you.
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Your ethernet cable is at least CAT 5e - better CAT 6 ?
Did you install the latest driver for the lan card ?
ftp://ftp.hp.com/pub/softpaq/sp43501-44000/sp43984.exe
or directly from Realtek:
http://www.realtek.com.tw/downloads/downloadsView.aspx?Langid=1&PNid=5&PFid=5&Level=5&Conn=4&DownTypeID=3&GetDown=false#RTL8111B/RTL8168B/RTL8111/RTL8168<br>RTL8111C/RTL8111CP/RTL8111D(L)<br>RTL8168C/RTL8111DPPlease copy complete link into your browser
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Gigabit LAN works with CAT-5, too FYI. Subjectively, I have only noticed a really small speed decrease, CAT-5e and 6 performs the same to me in normal circumstances (like not strapping the LAN cables with power ones).
@OP: A broken LAN plug can cause this sometimes but less likely. From what you said, it's either your driver or your laptop came with a Fast Ethernet LAN and not gigabit http://www.shopping.hp.com/series/category/notebooks/dv4t_series/3/computer_store?jumpid=reg_R1002_USEN .
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Gigabit LAN works with CAT-5, too FYI. Subjectively, I have only noticed a really small speed decrease, CAT-5e and 6 performs the same to me in normal circumstances (like not strapping the LAN cables with power ones).
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As 10/100 Mbit connections need only 4 wires of the cable and gigabit needs all 4 pairs, there is a difference. With a good Cat5 cable you might get a 1GB connection but many switches and/or network interfaces are refusing it and reverting to 100mbps.
This is not only theoretically spoken, I saw this with my old Compex and Netgear switches and some build in gigabit cards from Realtek and Marvell.
However some better Cat 5 cables may also work but to exclude this as source of error you should use Cat 5e or higher.
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CAT-5 only has only 4 wires, that is new to me. It's the problem of whoever choose to do the plug IMO. A badly did plug with CAT-5e or CAT-6 (CAT-6 is overkill and unnecessary under normal circumstances) can cause the same effect. That's why I said to check the plug. Most of the times, I have seen 1Gbps works fine with proper CAT-5 cable and plug. When it does not work, it's either like you said (some company decide to include cable with 4 wires with their network modem, router), or a badly done LAN plug. But that's that, the problem of the OP is he thought he has a gigabit interface and if I am to believe the spec page I linked to, then his belief is wrong.
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Ok a couple of important points.
100BaseTX uses 2 pairs, but the Cat 5+ cable used for Ethernet communications should still carry 4 pairs.
1000BaseT uses all 4 pairs.
1000BaseTX uses 2 pairs rated Cat 6 or better.
1000BaseT was written to require autonegotiation for gigabit operation, which is why it is not uncommon to see no option for it. It is also worth noting that the option you are talking about exists regardless of the cable used (you can set it before a cable is in place).
A lot of product are allowing manual lock down of port speed but it is a really bad idea, as it can lead to a duplex mismatch scenario in cases just like this. That said that option is not standard, it is above and beyond what the standard specifies.