My mate only turns his modem and homehub on when he needs them (via a energy saver set of sockets, turn PC on and it powers up modem and HH), has done ever since he got them in early 2011. He consistently get 70Mb down and 17Mb up.
So turning them on and off doesn't make any difference.
Thanks Ian, I'd been quietly hoping for someone to come along and say something like that ! I know it makes no difference if you do this on an ADSL connection, so i thought there was some hope that VDSL might be similar. I have no problems leaving equipment powered up if it's designed to be used that way, I'm just wary of doing it with cheapo plastic boxes especially when they and/or their power supplies get warm enough that the cat feels it worthwhile to sleep on top of them !
The modem is in constant talks with the fiber cab when the modem goes the fiber cab will try to reach it and it will keep dropping that IP Profile to do that, i've had a couple of problems that haven't helped, but i've unplugged the DSL and a minuet later plugged it in and done a BT speed test and it dropped the IP Profile, I don't know if it's just the modem that affects it but i'm as sure as hell not trying to switch off the HH3 as it's taken nearly a month of about 6 visits to get where i am, And i've been told and also experienced that the IP Profile can't be raised remotely you need to sit in a book an engineer to come round yay sounds fun........ not! If anyone can give something concrete on this it would be grate. Or i guess i'll have to wait and see when my Netgear comes as to weather the HH3 can go night night as long as the modem is on.
No problems with turning off really, other than when you do it multiple times in an hour/day making the system look unstable.
The DLM should really be able to tell the difference between the connection dropping due to the modem being unplugged etc, to the connection dropping due to problems on the line, if the dlm system can't even tell the difference then it needs updating so it can.
@Enigma, I have on occasions unplugged the hh3 and it's never afffected my speeds, the dlm doesn't care about the router, it's just paying attention to what the modem is doing.