Why wont my computer stay on! help

[420]

I recently made a computer (my first one) and i finally finished putting it back together and when i connected it up to a power supply it turned on for about 5 seconds then off then on etc. I took out the psu as me and my mate suspected it was this, i sent it away and it came back with no problems however the only other thing causing this would be the motherboard (GA-B85M-DS3H) if you know any other promblems or tips please reply thanks.

[TeKraken]

Try starting the PC with the bare minimum components installed.

1 stick ram
GPU (or onboard if you have it)
Cpu.

It should at least boot and be able to access the BIOS.

If that fails, try reseating your CPU heatsink and make sure all wires are connected/properly.

[420]

ok i will get back to you cheers!

[SteveO 5.0]

man there are so many possibilities. List your build, then check that all your psu connections have been made, your ram are in the motherboard specified slots, all connections are tight etc...

[chiefputsi✖️ping]

connection checklist:
1. 20+4pin main power connector
2. 4pin power connector (can also be 4+4pin power connector, depending on motherboard)
3, cpu cooler power connector

[_I_]

specs?

cpu, ram, psu(brand/model), gpu ect..

if its turning off, it could be heat or power supply related

[Bad_Motha]

Or a problem with how u mounted the motherboard.

Anytime I build, it's always a good idea to test your motherboard and components outside of the case first as a means of testing first or foremost.


How to safely setup and test your system outside of the case:
https://www.youtube.com/watch?v=YKhCQmKAmEM

[420]

my specs are:
GPU: MSI GTX 750 TI
MBO:B85M-DS3H
PSU:XFX 550W
OS:WINDOWS 8.1
CPU:INTEL i3 4150 3.5HGz
HARDRIVE:500GB WD BLUE
RAM:CORSAIR VENGENCE 2X4GB DDR3 1600

[Bad_Motha]

Ok; so what have u tried so far?

[420]

ive put it all together and it turned off on etc then i tried pushing all the cables in abit more nothing happend tried with one ram stick swaping etc changing sata thats it i think

[_I_]

make sure you plugged in the 4+4 pin eps power cable, top rear corner of the mobo

[420]

ive tried most of these things and none really have worked ugh!

[UNDEAD10000]

When you try turn your PC on, does it trying boot Win 8.1 before your PC turn off it self?

[420]

no nothing