OK to have WiFi set up and ethernet cabled to a PC? 2 September 2022 at 11:54PM in Techie Stuff 11 replies 411 views

JohnB47

I've just helped a friend replace an old WiFi Router with a new one. I connected up as per the existing cable connections, using all of the new cables, filter etc. I then powered on and set up the wifi by entering the network key and choosing 'connect'.

Some time later, I realised that having connected the PC to the Router using an ethernet cable, I needn't have set up wifi.

Presumably the PC still favours the hard connection but is there any harm in leaving it this way?

mgfvvc

Having Wifi on while using the Ethernet cable will probably result in a slighter higher power drain and your friend will have one less free Wifi channel.

shiraz99

JohnB47 said:

I've just helped a friend replace an old WiFi Router with a new one. I connected up as per the existing cable connections, using all of the new cables, filter etc. I then powered on and set up the wifi by entering the network key and choosing 'connect'.

Some time later, I realised that having connected the PC to the Router using an ethernet cable, I needn't have set up wifi.

Presumably the PC still favours the hard connection but is there any harm in leaving it this way?

No harm whatsoever.

Neil_Jones

JohnB47 said:

I've just helped a friend replace an old WiFi Router with a new one. I connected up as per the existing cable connections, using all of the new cables, filter etc. I then powered on and set up the wifi by entering the network key and choosing 'connect'.

Some time later, I realised that having connected the PC to the Router using an ethernet cable, I needn't have set up wifi.

Presumably the PC still favours the hard connection but is there any harm in leaving it this way?

Windows will favour whichever connection is faster, which will usually be the wired connection.

However don't expect it to be the case that if the wired connection is interrupted for whatever reason, Windows will use the wireless one straight away, because it won't.  You'd have to force its hand, usually via flight mode in and out to switch to the other connection.

unforeseen

However don't expect it to be the case that if the wired connection is interrupted for whatever reason, Windows will use the wireless one straight away, because it won't.  You'd have to force its hand, usually via flight mode in and out to switch to the other connection.

It should automatically switch over but takes a few secs, assuming that you haven't disabled LAN/WLAN switching in the BIOS. 

tallmansix

As per comments above all good, I have a laptop which spends most of the day plugged into a docking station on my desk with ethernet and it will always use that, but as soon as I disconnect the dock it switches to wireless instantly and seamlessly. When the dock is plugged in again, it will reconnect the ethernet.

mgfvvc said:

Having Wifi on while using the Ethernet cable will probably result in a slighter higher power drain and your friend will have one less free Wifi channel.

Nothing to do with wifi channels, they have exactly the same number of channels regardless of how many devices are connected.

JohnB47

Thanks everyone. I haven't done anything other than what I described, so I'll just leave it at that.

John_Gray

I've had both wireless and ethernet enabled on my laptop for years.  I can't recall encountering any associated problem...
Task Manager usually shows much more usage of the ethernet connection, because it's faster. 

mgfvvc

tallmansix said:

mgfvvc said:

Having Wifi on while using the Ethernet cable will probably result in a slighter higher power drain and your friend will have one less free Wifi channel.

Nothing to do with wifi channels, they have exactly the same number of channels regardless of how many devices are connected.

I might have phrased that incorrectly. You can only connect so many devices to a router before DHCP runs out of available IP addresses and using one for a redundant Wifi connection reduces the number available. It would be unusual for that to matter in an ordinary domestic setup.

unforeseen

Actually, the amount of memory allocated for the DHCP & NAT tables are the limiting factor.
In theory, if you use 10.x.x.x IP with the normal B class subnet you have 64k IP addresses available but will run out of memory before you get anywhere close to that. The tables are normally good for 64-100 different devices. 

KingsleyBriggs

yes, its should switch on it's own.