Gigabyte 4870 display issues

[deepsol]

I'm building a new computer and when I turned it on for the first time all the lights and fans turn on, except nothing shows on the screen, only the no signal message. Also, three lights flash on and off on the side of the graphics card.
I have the two power cables plugged in, one dedicated and another with adaptors, but could it be the PSU if it stays on flashing until I turn it off?
I have also tried another graphics card, nVidia 8400 and nothing showed up.
My motherboard is a GA-MA790X-DS4 and maybe that is the problem?

 

[jitpublisher]

Did you plug in the 4 pin CPU power connector on the board? This is the most overlooked cause of a new system not booting.

 

[ckaz]

I had this issue but with different components, so I will do my best to help. I'll start off first by asking, what sort of connection are you using (VGA, DVI, HDMI)?

 

[mystic84]

I'm building a new computer and when I turned it on for the first time all the lights and fans turn on, except nothing shows on the screen, only the no signal message. Also, three lights flash on and off on the side of the graphics card.
I have the two power cables plugged in, one dedicated and another with adaptors, but could it be the PSU if it stays on flashing until I turn it off?
I have also tried another graphics card, nVidia 8400 and nothing showed up.
My motherboard is a GA-MA790X-DS4 and maybe that is the problem?

Check 6-Pin or 2x 4-Pin -> 6-Pin Connector is plugged in.
If it has 2 on the card You need 2 Plugged in.
Check wattage of power supply and manufacturer if not confident on power.

Hope it helps

 

[mystic84]

These 4-Pin to 6-Pin Connectors are in the Graphics Card Box, If you didn't get a box demand it from the store (or at least the connectors you need).