New Computer wont stay on anymore

[hoback48]

Compaq presario SR2163WM

started running real slow...wife and kids hard booted several times till it would not show anything but black screen...froze up.....powered down unplugged all power removed fan and heat sink for CPU...was horribly dirty. reassembled and now it wont even stay powered up... turns on ans stays for just a few seconds then shuts itself down... disconnected 4 wire harness to mother board i think for cpu and stays on....no display but stays on....any ideas please???

 

[guavasauce]

yeah, you need the 4 and 24 pin plugged in. when you removed the heatsink, did you reapply thermal paste before reseating the sink? and did you plug the cpu fan back in? sounds heat related.

 

[hoback48]

yeah, you need the 4 and 24 pin plugged in. when you removed the heatsink, did you reapply thermal paste before reseating the sink? and did you plug the cpu fan back in? sounds heat related.

did not replace any paste...not that knowledgeable im afraid... it stays on for roughly 3 to 5 secs...could that be due to paste

 

[hoback48]

fans come on properly display starts on monitor but just shuts down within 5 secs

 

[hoback48]

both 4 and 24 were plugged in when i removed and cleaned heat sink...all back together , fans work, old past still in place but not new, i removed the 4 pin troulble shooting from another web site to see if it stayed on and it did with 4 pin disconnected, but shuts down in 5 connected, not sure that it means anything what so ever, checked power from 4 pin but not sure what i should read.. was less that a volt

 

[hoback48]

Does anyone know what might be my problem with this pc...i am clueless here