GA-X58A-UD3R Rev2, no POST or Beeps

[Chobtime]

Hello there Gigabyte members, Ive got a GA-X58A-UD3R Rev 2, after installing a Nvidia 8400 Graphics card I was hoping to see the BIOS for the time, but I don't get any picture or video signal at all, nor do I receive any notification beeps from the speaker I attached to the motherboard, it appears to have some fault that is causing it not to POST at all :/ The CPU and RAM LEDs light up and power from the mobo goes into the connected fans, I even did a bench test but still nothing.
i've already messaged Gigabyte and waiting for a reply but I thought Id make a post about it here to see If anyone could offer any suggestions. thank you all.

[Dark Mantis]

Hi and welcome to the Gigabyte Forum.

Perhaps you could post what PSU make/model you have installed?

Have you checked that the buzzer is connected the correct way round as they are polarity concious?

What slot have you installed the GPU in?

What slots are the memory modules in?

Have you connected the 12v EPS connection near the CPU?

[Chobtime]

You are a life saver, I didnt realise the ATX 12v had to be connected Dx thank you so much!! <3

[Dark Mantis]

You are very welcome and it's nice when they are so easy.