Like i said i have no idea about mIRC 'lingo' so your first statement doesn't make sense to me (although it is probably quite easy i am quite new to this)

I tried all 3 :

/server 83.149.112.71
/server 174.34.173.51
/server 78.159.100.188

Getting this message each time :

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(15:49:05) * Trying to reconnect in 10 second(s)
(15:49:15) * Connecting to 174.34.173.51 (6667)...
(15:49:36) Error connecting to 174.34.173.51: No reply from server. The server may be currently experiencing difficulties. This error could also indicate a problem with your Internet connection. If your connection is otherwise working, security software (firewalls, anti-virus etc.) may be blocking access to IRC.
(15:49:36) * Trying to reconnect in 10 second(s)

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This on mIRC:

* Unable to connect to server (Connection timed out)
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* Connect retry #3 78.159.100.188 (6667)
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I am also unsure as to what you mean by :
"(Reverse DNS entries for above IP addresses)
ixion.nl.eu.swiftirc.net
purple.swiftirc.net
deathknight.net "
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