Sign in with
Sign up | Sign in
Your question
Solved

7970 Ghz no signal detected on boot with 8 pin and 6 pin, boots fine with only 8 pin

Tags:
  • Graphics
Last response: in Graphics & Displays
Share
August 29, 2013 6:14:40 AM

Hi guys,

I just finished my first build and have a bit of problem. The computer boots up fine to the bios with all fans spinning and everything when I have only the 8 pin connected to my XFX 7970 Ghz card, but when I connect both the 6+2 and 6 pin to the card, my monitor shows no signal detected.

I had believed the gfx card requires both 8 + 6 pin connections? Also note that I read on a review the card may require 2x 6 pin connectors, but when I tried only using the two 6 pin connectors, I get the same no signal detected error.

The PSU is an Antec 520W modular with 2 6+2 pin connectors split from the 1 cable.

Is there something wrong with my graphics card? Or is the PSU simply not compatible with that card? I'm a bit lost here.

Cheers for any advice you can give me

More about : 7970 ghz signal detected boot pin pin boots fine pin

Best solution

August 29, 2013 6:30:13 AM

Most likely your PSU can drive the single 8pin with high enough voltage and amps to run your GPU at low power need situations.
But when you connect the 'split' cable to both it no longer provides enough juice for the 8pin.
So either you can try to connect the 2nd 6 pin from another location or you are going to have to get a new PSU.
On that note newegg is running a great sale on the HX750. $109.99 ( and $20 MIR )
Share
Related resources
August 29, 2013 6:45:45 AM

rvilkman said:
Most likely your PSU can drive the single 8pin with high enough voltage and amps to run your GPU at low power need situations.
But when you connect the 'split' cable to both it no longer provides enough juice for the 8pin.
So either you can try to connect the 2nd 6 pin from another location or you are going to have to get a new PSU.
On that note newegg is running a great sale on the HX750. $109.99 ( and $20 MIR )


rvilkman said:
Or if the HX750 is too expensive:
This seasonic S12II 750 is nice as well for 79.99 ( and $20 MIR )


So you think it's an issue with the PSU and not the GFX? I also live in Australia so can't buy from Newegg. Hopefully if it's a PSU issue I can just take it back on warranty and get it replaced. I
m
0
l
August 29, 2013 7:05:03 AM

aotengs said:
rvilkman said:
Most likely your PSU can drive the single 8pin with high enough voltage and amps to run your GPU at low power need situations.
But when you connect the 'split' cable to both it no longer provides enough juice for the 8pin.
So either you can try to connect the 2nd 6 pin from another location or you are going to have to get a new PSU.
On that note newegg is running a great sale on the HX750. $109.99 ( and $20 MIR )


OK well it's probably kind of a compatibility issue with the PSU and GPU. Not enough power to run the GPU. So the PSU is probably find, just not good enough to run a powerful card like the 7970 Ghz.
rvilkman said:
Or if the HX750 is too expensive:
This seasonic S12II 750 is nice as well for 79.99 ( and $20 MIR )


So you think it's an issue with the PSU and not the GFX? I also live in Australia so can't buy from Newegg. Hopefully if it's a PSU issue I can just take it back on warranty and get it replaced. I


m
0
l
August 29, 2013 7:33:42 AM

rvilkman said:
aotengs said:
rvilkman said:
Most likely your PSU can drive the single 8pin with high enough voltage and amps to run your GPU at low power need situations.
But when you connect the 'split' cable to both it no longer provides enough juice for the 8pin.
So either you can try to connect the 2nd 6 pin from another location or you are going to have to get a new PSU.
On that note newegg is running a great sale on the HX750. $109.99 ( and $20 MIR )


OK well it's probably kind of a compatibility issue with the PSU and GPU. Not enough power to run the GPU. So the PSU is probably find, just not good enough to run a powerful card like the 7970 Ghz.
rvilkman said:
Or if the HX750 is too expensive:
This seasonic S12II 750 is nice as well for 79.99 ( and $20 MIR )


So you think it's an issue with the PSU and not the GFX? I also live in Australia so can't buy from Newegg. Hopefully if it's a PSU issue I can just take it back on warranty and get it replaced. I




Ahh damn... and to think all the posts I've read where people have had concerns about sufficient wattage and everybody saying ~500w is fine ;/. I suppose I will try and get it replaced
m
0
l
August 29, 2013 9:27:03 AM

Yeah the wattage should be it's probably just how your PSU is wired which is causing your issues. Btw what exactly is the model of your PSU. Is it the eco series or the high current gamer series ?
m
0
l
August 29, 2013 3:39:28 PM

It's the HCG series 520watt modular
m
0
l
August 29, 2013 3:41:37 PM

I just found out I made a pretty big FUBAR.... Turns out I had plugged in the hdmi cable to the integrated graphics port on my mobo and not the gfx card itself. I have work now so I won't be able to test it plugged in to the gfx until tonight... but do you think that might have been the problem why it wasn't posting when I had both pins connected to the gfx? Something to do with the mobo trying to get display from the card since all the connectors are in, but the cable was in the integrated port
m
0
l
August 29, 2013 3:59:00 PM

aotengs said:
I just found out I made a pretty big FUBAR.... Turns out I had plugged in the hdmi cable to the integrated graphics port on my mobo and not the gfx card itself. I have work now so I won't be able to test it plugged in to the gfx until tonight... but do you think that might have been the problem why it wasn't posting when I had both pins connected to the gfx? Something to do with the mobo trying to get display from the card since all the connectors are in, but the cable was in the integrated port


A bit hard to say, but a HCG-520 should be able to run that card. Even though the 'max load' for the 12V is 'only' 480W still it should run fine. But yeah give it a try, plug the cable to video card properly, plug in your PCIe's and see if you get a picture. If not then make sure that your bios also has the display settings setup so that it tries from PCI first instead of the onboard or on-chip graphics, at least i had to do that for my Asus board.
m
0
l
!