WIFI dies when external monitor is activated

[TwanK]

Hi,

Since end of September with Ubuntu 9.04 till 9.10 today, I have problems with my wifi. Ping times to my router a few meters away vary up to 20 seconds. Today I found out that I can influence the behaviour by activating or deactivating my external monitor. Even when the cable is still attached (no earth loop obviously), but the screen is not activated (System > Preferences > Display), the wifi stays intact.

A fresh Karmic from USB shows the same behaviour.

I noted that i916 and ath5k share the same interrupt (irq16), could that be the problem? Or has the Intel driver or ath5k driver been updated somewhen end of September in the official Ubuntu repository (I don't use the Voria repository).

Please help me out.

TwanK
Samsung N110 - Ubuntu 9.10

[voria]

Hello,
it's the first time I read of this problem, I don't know how to help you, I'm sorry.
If it's really an irq sharing issue, have you tried to update to latest BIOS, if any new is available?

[TwanK]

Hi,

I'm running with the latest Bios and WinXP works flawless.

Twan

[TwanK]

in addition, I just discovered that when the internal and external screen are both active: wifi stays intact. only when the internal screen is shut off, then the wifi speeds goes down dramatically.

Twan