> G5 ( os x ) ; cat5 cable
> PC ( xp ) ; wireless G
[quoted text clipped - 7 lines]
>
> does anybody know what could be the problem ??
Might be because of bad cable. Or because of inconsistent speed/duplexness
settings on G5 and wrt54gs. The "ifconfig en0" command should show you
something very similar to this:
# ifconfig en0
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
inet 1.2.3.4 netmask 0xffffff00 broadcast 1.2.3.255
ether 00:30:65:8f:be:a0
media: autoselect (100baseTX <full-duplex>) status: active
^^^^^^^^^^^^^^^^^^^^^^^
Unfortunately, I don't know whether is it possible to get similar information
on the Linksys router, but maybe on the G5 end you'll notice something unusual.

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andrei