My ol' ultrasharp 2407WFP is showing signs of old age

so I am in the market to find a new IPS type LCD to replace the old PVA one

so my current one is 1920x1200rez coupled with a 42" LCD TV @ 1920x1080rez

Last I heard, nvidia and amd new GC cards is a b**** in power saving, as the different resolution monitor sort of disable the power saving feature
I dun do dual monitor, only for like playing movies and such will I use the LCD TV
but the HDMI cable is always connected.

so is it better to get a new Dell U2312HM @ 1080 or a Dell U2412M @ 1200
have got used to the 1200 rez for ~5 years already

it the 120 lines gonna be missed?