Question Pc no longer powering on when GFX card is powered from pci-e

Oct 9, 2020
8
0
10
0
Hey all,

So I was doing a bit of work life balance today (I.e. gaming while in a teams meeting) when my rig shut down randomly. I assumed this was due to having some edge windows open and running out of ram so I (stupidly) tried again. Same result, cut to black after a few mins.

Now the problem is that I have no response from the computer when I try to turn it on. I've unplugged everything except the monitor and power supply and there's no response.

The weird part is, the computer works with no GFX card installed and running off integrated. When I plugged the card in and forgot the pci-e power, I got the screen telling me to plug it in and the LEDs on the GPU lit up. On plugging the pci-e power back in it goes back to being non-responsive.

What's your thoughts guys? I'm leaning towards a boned gpu. But I'm going to see if I have a second 8->8+6 cable lying around incase the cable is fried. Many thanks for any responses.

Rig:
I5 6600k
Evga 980 Ti
16gig gskill ripjaws v
Asus gene VIII mono

Thanks!
 
Oct 9, 2020
8
0
10
0
I've tried the following:

  • Card in an alternative PCI-E slot
  • Alternative power socket on the power supply
  • Alternative 8pin to 6+2 & 6 pin cable
The system runs fine on integrated graphics, once the card is removed. If inserted but not powered using the cable, the LEDs light and fans spin but obviously it requests PCI-E power.

On inserting the PCI-E power cables, the system is entirely unresponsive. Pressing the power button does absolutely nothing.

I'll try clearing the CMOS but unclear as to how this will help given that it boots fine on IG.
 
I've tried the following:

  • Card in an alternative PCI-E slot
  • Alternative power socket on the power supply
  • Alternative 8pin to 6+2 & 6 pin cable
The system runs fine on integrated graphics, once the card is removed. If inserted but not powered using the cable, the LEDs light and fans spin but obviously it requests PCI-E power.

On inserting the PCI-E power cables, the system is entirely unresponsive. Pressing the power button does absolutely nothing.

I'll try clearing the CMOS but unclear as to how this will help given that it boots fine on IG.
What is the brand, model name/number and age of the power supply?
 
Oct 9, 2020
8
0
10
0
What is the brand, model name/number and age of the power supply?
EVGA Supernova 850 Gold, bought in 2015, brand new. Still functions powering the rest of the PC and turns on the lights and fans on the card through the PCI-E slot, provided the cables aren't connected!
 
EVGA Supernova 850 Gold, bought in 2015, brand new. Still functions powering the rest of the PC and turns on the lights and fans on the card through the PCI-E slot, provided the cables aren't connected!
There are 4 different supernova models, maybe more. Which one do you have? This is why I asked for model specifics. G3, GA, G2, G1+ ??

It's unlikely to be the PSU but it has to at least be considered. If your GPU drivers are up-to-date and you're sure the fans on the GPU are working but no display, the GPU may have died. One test is to try iGPU which you already did. The only other way to be sure is to test with another GPU.
 
Last edited:
Oct 9, 2020
8
0
10
0
In my head, I've narrowed it down to either the VGA power ports on the PSU, or the GPU.

I may have another GPU kicking around somewhere to test but....it's gonna be an old one, I'd be better off running the iGPU
 

groo

Distinguished
Feb 3, 2008
1,046
5
19,295
1
I would start with;
Check for shorts when poweredoff (both sides)
Check for proper voltage from all hots to all grounds on the psu side when powered up.
 
Oct 9, 2020
8
0
10
0
Okay, so I couldn't find my multimeter. Got one on order. I did pick up a fast delivery on a psu tester though.

Amazon link

On plugging into mobo it lights up fine. Plugging in either the 6+2 or the 6 pin connector does nothing. I'm wondering now if the PCI-E power is supplied off a different rail internally and this has fried.

A few questions in my head:
A: would the entire pc not boot if a graphics card was installed with no power? Seems odd as the computer will start if the card is in the slot with no pci-e power connected.
B: are supply cables always powered when plugged into the supply or do the "sense" pins perform a switching role, and only supply when plugged in? I cannot connect the +2 pin to my tester so was wondering if this could cause the lack of supply.

Any advice appreciated.
 
Oct 9, 2020
8
0
10
0
I would start with;
Check for shorts when poweredoff (both sides)
Check for proper voltage from all hots to all grounds on the psu side when powered up.
Sorry to ask what's probably a simple question but, how would I check for shorts on the card side?

Thanks in advance!
 

groo

Distinguished
Feb 3, 2008
1,046
5
19,295
1
If the sense pins sense a ground plugged it, the card thinks it has power. When I don't plug in the aux power on my card, it gives a message to the screen, something about 6 pin power connector not plugged in. Just like a line of red text at the top of the screen. It still displayed something for me is I guess what I am saying. Mine is a very old card, so I have my doubts a new card wouldn't handle doing at least that much.
 

ASK THE COMMUNITY

TRENDING THREADS