hp compaq NC6400 no power

ok well I was rebuilding an old hp compaq nc6400 had just put the new hard drive in and installed the os ... then today I tried to power it on ... (I had been getting a cmos battery dead warning as well had planned to replace it as soon as it arrived) and well It did nothing while plugged into the charger no lights flashin the charging symbol ... when I unplugged the charger the computer power button light would click on then the battery light would click on (this is a brand new replacement battery) (and a brand new replacement charger) (I also checked with another charger to make sure that the charger wasn't faulty and no response) flashing like the battery was dead I waited a while with it charging and reattempted to make sure that the battery wasn't so low that it was affecting it ... no dice ... I removed the battery and tried directly from charger no dice ... I tested another cmos battery I had laying around (unknown if that battery is working at all) so im unsure where to proceed from here any ideas would be greatly appreciated ... I am quite sure that computer hasn't been overheated as all I did was install and yeah so imunsure any help ideas input would be greatly appreciated