Waste of time , seriously, those recorders you can't even give away now, even swann has overtaken it
So you will be like trying to fit ip 720p or something like that
It will only record in analogue resolutions even if converted, not recommended.
Some machines are "hybrid" so you map IP's to the channels, this usually requires PoE elsewhere and detecting cams from the WAN.
Just replace the lot with new Samsung. Seems a shame to get rid of a decent DVR but if 960H isn't good enough now (new cams?), you need to start again.