This is crazy. Someone must have made a mistake. I just got my work monitor shipped to me today and was plugging it in and testing it. After I did so I could not get wifi to work. Wifi has worked flawlessly from my office using a similar Macbook Pro in the past. The wifi was working for my wife’s Mac Mini downstairs. Why did the wifi suddenly stop? The answer: the monitor is killing my wifi connection.
I still see “4 bars” of wifi on the little gauge at the top, but nothing is going across that excellent connection. I can repeat this experiment over and over and the pings tell all:
64 bytes from 192.168.1.1: icmp_seq=100 ttl=64 time=1.563 ms 64 bytes from 192.168.1.1: icmp_seq=101 ttl=64 time=1.555 ms 64 bytes from 192.168.1.1: icmp_seq=102 ttl=64 time=1.333 ms 64 bytes from 192.168.1.1: icmp_seq=103 ttl=64 time=1.507 ms 64 bytes from 192.168.1.1: icmp_seq=104 ttl=64 time=1.585 ms 64 bytes from 192.168.1.1: icmp_seq=105 ttl=64 time=1.558 ms 64 bytes from 192.168.1.1: icmp_seq=106 ttl=64 time=1.553 ms 64 bytes from 192.168.1.1: icmp_seq=107 ttl=64 time=2.514 ms 64 bytes from 192.168.1.1: icmp_seq=108 ttl=64 time=1.571 ms 64 bytes from 192.168.1.1: icmp_seq=109 ttl=64 time=1.333 ms 64 bytes from 192.168.1.1: icmp_seq=110 ttl=64 time=1075.141 ms 64 bytes from 192.168.1.1: icmp_seq=111 ttl=64 time=78.932 ms 64 bytes from 192.168.1.1: icmp_seq=112 ttl=64 time=5909.617 ms 64 bytes from 192.168.1.1: icmp_seq=113 ttl=64 time=4909.318 ms 64 bytes from 192.168.1.1: icmp_seq=115 ttl=64 time=15571.986 ms 64 bytes from 192.168.1.1: icmp_seq=116 ttl=64 time=14588.171 ms 64 bytes from 192.168.1.1: icmp_seq=117 ttl=64 time=13587.816 ms 64 bytes from 192.168.1.1: icmp_seq=118 ttl=64 time=12587.626 ms 64 bytes from 192.168.1.1: icmp_seq=119 ttl=64 time=11590.435 ms 64 bytes from 192.168.1.1: icmp_seq=120 ttl=64 time=10591.978 ms 64 bytes from 192.168.1.1: icmp_seq=121 ttl=64 time=9592.633 ms 64 bytes from 192.168.1.1: icmp_seq=122 ttl=64 time=8593.659 ms 64 bytes from 192.168.1.1: icmp_seq=123 ttl=64 time=7594.748 ms 64 bytes from 192.168.1.1: icmp_seq=124 ttl=64 time=6595.005 ms 64 bytes from 192.168.1.1: icmp_seq=125 ttl=64 time=5601.815 ms 64 bytes from 192.168.1.1: icmp_seq=126 ttl=64 time=4603.203 ms 64 bytes from 192.168.1.1: icmp_seq=127 ttl=64 time=3603.183 ms 64 bytes from 192.168.1.1: icmp_seq=128 ttl=64 time=2603.059 ms 64 bytes from 192.168.1.1: icmp_seq=129 ttl=64 time=1612.565 ms 64 bytes from 192.168.1.1: icmp_seq=130 ttl=64 time=612.293 ms 64 bytes from 192.168.1.1: icmp_seq=131 ttl=64 time=1.103 ms 64 bytes from 192.168.1.1: icmp_seq=132 ttl=64 time=1.346 ms 64 bytes from 192.168.1.1: icmp_seq=133 ttl=64 time=1.428 ms 64 bytes from 192.168.1.1: icmp_seq=134 ttl=64 time=1.459 ms 64 bytes from 192.168.1.1: icmp_seq=135 ttl=64 time=1.516 ms 64 bytes from 192.168.1.1: icmp_seq=136 ttl=64 time=1.444 ms 64 bytes from 192.168.1.1: icmp_seq=137 ttl=64 time=1.599 ms
You can see my normal pings to my router are around 1.5 milliseconds. The hop up to 1 second happens at icmp_seq 110 when I plugged the monitor in. You’ll note from there that nothing got out until I unplugged it after about 15 seconds. You can tell by looking at 115 to 130. The first, 115, is one second higher than 114. This pattern continues down until 130. They’re one second apart because that’s how fast ping was firing them. Nothing got out while the monitor was plugged in, but they immediately got out and were all responded back to at the same time as soon as I unplugged the monitor.
This is a very interesting phenomenon and one I’ve never encountered before.
Weird.
Update June 8, 2008: Wireless-N to the rescue. I bought a LinkSys WRT160N to replace the wireless of my LinkSys WRT54G and my problems are solved. My wifi access is considerably faster to boot. Cheers.
Is this one of those monitors that pulls power from the video card? It could be that the extra power pulled drops the signal strength coming out of the wifi antenna.
The most likely culprit to me, however, is interference. Ping demonstrates a symptom, but not helpful in making a diagnosis. If you can plug in the monitor and measure the noise floor the card perceives, that'd be peachy. Alternatively, grab your closest high frequency spectrum analyzer and tune it into the 2.4Ghz range and watch what happens when you power on that monitor.
Nope, it's nothing fancy. Just a humongous flat panel.
I found that plugging directly into the wall helped some, but not enough to matter (wifi dies completely after about 10 seconds rather than instantly). I'm thinking of upgrading my wifi to 802.11n anyway, which will probably help. This may be the event that motivates me to finally wire my office too.