ok heres the situation
i just replaced a dc jack that was solder to motherboard on a acer 1690 laptop , i put part of it it all back together to try the power see if it was working the fan came on power lights came on i thought great it works, the fan went off after about 3-4 seconds but the power light and other lights stopped on i thought the fan will keep going when i add the monitor, hdd ,and all the rest of the laptop. so i put it all back together and tried it again , fan came on lights came on that was it ? no monitor no hdd did not even boot into first part of screen where you can get into bios then i checked the fan and turned it on and off 3-4 times and notice the fan was doing the same again coming on for 3-4 seconds and knocking off ,i dont think i missed anything putting it back and the lights stop on and the laptop turns off after i press power button for 4 seconds as normally. its just that it don't want to boot and the fan stops and does not even get the the acer screen ,when i was soldering , the solder was a bit shabby ,now could it be a short somewhere i not good at soldering i know when i soldered on one part of the dc jack did not fit into the hole right when i solder it but it did get contact with the board or could it be something else i have re tried everything a few times and still the same when i turn it back on.
the laptop 6-7 years old and the part was 5 dollars the point i did it myself was to save money due to it will cost from 75-130 dollars to repair and not worth it to repair at over 75 dollars thats if its a soldering problem
i wondering if it is a dry joint or my bad soldering anyone else any ideas