Question Gpu fans dont spin and no display everything else looks to work fine

[Timefree]

I have salvaged the gpu,psu and ram from a pc that worked this morning. I upgraded the mobo and cpu from a fx4100 to i5 4960 and the cpu fans seem to work , pled is on, all pc leds are on, even gpu leds are on,but the fans start spinning on boot and immediately turn off, while everything else is still working fine and there is no signal to my monitor.

I tried- changing gpu, checked ram, changed psu, changed hdd

Specs : 1050ti 4g asus strix I5 4960 with asus h81m-e (upgraded from fx 4100 and some random motherboard) 16gb 1333mhz ddr3 ram Seagate 1tb hdd 5200rpm Arctic alphine 12 cooler Corsair cx600m psu

 

[NightHawkRMX]

Does it boot with monitor plugged into motherboard?

 

[Timefree]

i am not sure as i dont have a vga cable

 

[Timefree]

update let it run in the background for 30mins. still no display, the fans didnt start either but the gpu mobo and hdd warmed up which makes me think that they are working