New build doesn'twork

I'm looking for help with a build that will not run.

In short, with the PC powered on, the CPU cooling fan runs and the hard drive runs but there is no light from the optical mouse and the keyboard LED's won't come on. There's also no video.

The components:

Gigabyte GA-78LMTUSB3 mother board

XFX TS550 power supply

Crucial Ballistix Sport 8GB Kit (4GBx2) DDR3 1600 (PC3-12800) 240-Pin UDIMM Memory


I suspect I made an error in installing the power supply, possibly with the ATX 8-pin connector. Power supply documentation is sparse.

Any suggestions of what I did wrong?

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Have you applied the correct standoffs to the board? One more extra could possibly short the board.

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Listen to tyler2times.

This is one of the reasons I build a new rig on cardboard first. To be sure it all plays together. I only need a few basic parts. Don't need the HDD, ODD or SSD or all the RAM.

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You have a power problem
there is no light from the optical mouse and the keyboard LED's won't come on. There's also no video.

keyboard and mouse have no power and that's the 5v circuit. I'm assuming they are corded. PCI is 3.3v and 5v

Try a different PSU.
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PCI bus info
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What type of keyboard you have.

If it's not ps2. borrow one and try it.

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