Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I bought a Buffalo WZR-HP-G450H router.


8 device connected to it via wireless. When power it on, the connection speed is very fast, about 5MB/s while transfer files between a wired server and my laptop using wireless.

But when run almost 20 hours later, the speed is quite slow, about 50-100KB/s. Ping the wired server, will get about 20% package lost, and response time various from 200ms to 2000ms. No one is transfer files at that time except me.

What's wrong with my router? Is setup error?

I have another Linksys router which setup is the same, that works fine for years.

Network Environment

We have a Cisco Switch, the router connected to the switch, and will act as an AP to extend the wired network.

I flashed the firmware to "Buffalo DD-WRT v24SP2-MULTI (09/27/12) std"

On this router, I switch off DHCP Server(we have another DHCP Server running), assign an IP Address with Mask, and Gateway is, DNS Server is

In wireless setup page:

  • Wireless Mode is "AP", can select "Client", "Client Bridge", "Adhoc", "WDS Station", "WDS AP"
  • Wireless Network Mode is "Mixed", because there are some old device in our office.
  • Channel Width is "40Mhz", because I want use 450Mbps
  • Wireless Channel is "1"
  • Extension Channel is "upper"
  • Advanced Settings is "Off"

In Status page:


  • CPU Model Atheros AR7242 rev 1.1 (0x1101)
  • CPU Clock400 MHz
  • Load Average 7% 0.08, 0.08, 0.05


  • Total Available 94% 61428 kB / 65536 kB
  • Free 71% 43528 kB / 61428 kB
  • Used 29% 17900 kB / 61428 kB
  • Buffers 13% 2344 kB / 17900 kB
  • Cached 37% 6704 kB / 17900 kB
  • Active 26% 4684 kB / 17900 kB
  • Inactive 33% 5924 kB / 17900 kB

Space Usage

  • NVRAM 21.38 KB / 64 KB
  • CIFS(Not mounted)
  • JFFS2(Not mounted)


  • IP Filter Maximum Ports 4096
  • Active IP Connections 1% 61

Wireless Packet Info

  • Received (RX) 100% 8406197 OK, no error
  • Transmitted (TX) 100% 11504216 OK, no error

Wireless Status

  • Mode is "AP"
  • Network is "Mixed"
  • Channel is "1 (2412 MHz)"
  • TX Power is "25.5 dBm (EIRP av.)"
  • Rate is "450 Mb/s"
  • ACK Timing is "15┬Ás (2250m)"
  • Encryption - Interface ath0 is "Enabled, WPA2 Personal"
  • PPTP Status is "Disconnected"


share|improve this question

You must log in to answer this question.

Browse other questions tagged .