New build with no POST or USB power - what else can I try?

Brynjaminjones

Distinguished
Oct 13, 2009
6
0
18,510
I'm sorry if this has been asked 1000x before, but I'm just looking for some advice specifically related to my setup.

I've just assembled a computer with the following components:
Intel i5-4460 with stock cooler
MSI B85M-P33 Mobo
Corsair XMS3 1600MHz RAM (1x4gb)
Seagate 7200.12 1TB HDD
Corsair CX430 modular PSU

It all assembled fine, but when started up there is no POST or power to USB devices (no lights on keyboard).
The fans and hard drive all spin up, and the DVD drives will open and close.

I've tried both RAM slots, I've done a CMOS reset, I've tried VGA and DVI ports on the mobo, I've breadboarded it (taken mobo out, disconnected everything except RAM, CPU, cooler, PSU, power switch, monitor and keyboard). All of this was to no avail.

I've not built a computer since I was about 14 in 2008, and I'm really stuck with this. I'm building it for my sister, and desperately want to get it working!
Can anybody help?
 
Which USB ports are you connecting the keyboard to? In older builds, only the rear USB 2.0 would be detected by BIOS and you'd have to load drives in Windows for USB 3.0 and some headers controlled by non-integrated controllers to operate.

Also for front USB, did you connect the USB header cables?