what kind of liquid cooling ? We talking CLC or "real" liquid cooling with adequately sized pumps and copper radiators ?
Your fans must exactly match the radiator ... use 120mm fans on 120mm wide rads. The HAF-X isn't a very good case for liquid cooling. The CM site makes no mention of radiator support for the HAF ... tho it should have plenty of room to fit it, there's no mentions of providing the necessary support for the rads and fan mounts. At the very list, I expect you will have to toss the 200m fans an mount two 140mm fans on a 280 or three 120mm fans on a 360 underneath
That being the case, brings me back tot he 1st question.... Unless you are considering a custom loop or all-in-one system from Swiftech or EK, there is no CLC that actually outperforms an equivalently priced air cooler.
Depending on Budget ... if ya keep the case....
$50... Mugen Max
$60-$65 ... Phanteks PH-TC14-PE
$90 ... Noctua NH-D14
$165 .... Swiftech H320 X2 -
http://www.swiftech.com/h240x2.aspx
$150 .... Swiftech H240 X2 -
http://www.swiftech.com/h240x2.aspx