Question Specific gpu doesn't work on specific motherboard

[Ineocla]

Hi everyone.
Recently i wanted to test an older GPU i had lying around so i removed my perfectly working GPU and put it on my mobo. But when i put it back it didn't work at all. Like no fans spinning and no signal. I took it to a shop and he tested the GPU on another system and it worked fine. He tried multiple other gpus on my mobo and they all worked fine too except mine. He tried clear CMOS, BIOS update, different psu, different RAM nothing worked. I'm kinda out of options right now and so i'd like to have some suggestions from you guys before i go ahead and buy a new mobo.

CPU : i7 10700k
GPU : RX 6800
Mobo : asus tuf z590 plus wifi
Psu : corsair CX 750w bronze

 

[SkyNetRising]

i'd like to have some suggestions from you guys before i go ahead and buy a new mobo.

Did you try graphics card in second PCIE slot?

 

[Ineocla]

Did you try graphics card in second PCIE slot?

Yup i tried and it didn't work either

 

[SkyNetRising]

But when i put it back it didn't work at all. Like no fans spinning and no signal.

What did you mean by this?
No fans spinning on graphics card only?
Or no fans spinning at all, not cpu fan, not any system fan?

If second option, then you're probably are using wrong modular psu cables to connect graphics card.
Modular psu cables are not compatible between different psu models.
Using wrong modular cables can kill/damage hardware connected.

 

[Ineocla]

What did you mean by this?
No fans spinning on graphics card only?
Or no fans spinning at all, not cpu fan, not any system fan?

Only the gpu. The whole system works fine including the igpu of the processor. And btw the cable i used in this gpu is the same as i used in my previous gpu so that can't be the problem

 

[mmp09]

Did the technician at the shop comment something? Did they try another PSU on your system?

 

[Ineocla]

Did the technician at the shop comment something? Did they try another PSU on your system?

Yes he tried another psu. He also couldn't find anything physically wrong with neither the gpu or the motherboard

 

[mmp09]

May be try to clean the PCIe slot with spray of 99.9% pure IPA cleaner.
It could be that the slot has some dust or other particles preventing firm contacts with the card.

 

[Ineocla]

May be try to clean the PCIe slot with spray of 99.9% pure IPA cleaner.
It could be that the slot has some dust or other particles preventing firm contacts with the card.

I'll try but i doubt it since other gpus worked on the same slot

 

[mmp09]

I understand...just give it a try

 

[Ineocla]

I understand...just give it a try

As expected still nothing. One thing i forgot to mention was that the back of the gpu does heat up and the VGA led on my motherboard lights up white indicating that the post was successful

 

[SkyNetRising]

and the VGA led on my motherboard lights up white indicating that the post was successful

If VGA led remains lit, this means there was a problem with VGA during POST.
With successful POST all diagnostic leds would turn off.

 

[Ineocla]

If VGA led remains lit, this means there was a problem with VGA during POST.
With successful POST all diagnostic leds would turn off.

No an error is indicated by a red light on this motherboard. In this case it's a white light followed by the boot light turning on

 

[SkyNetRising]

No an error is indicated by a red light on this motherboard. In this case it's a white light followed by the boot light turning on

No.
Read user manual of your motherboard.

The Q-LEDs check key components (CPU, DRAM, VGA, and booting devices) during
the motherboard booting process. If an error is found, the critical component’s LED
stays lit up until the problem is solved.

BOOT (YELLOW GREEN)​

VGA (WHITE)​

DRAM (YELLOW)​

CPU (RED)​

https://dlcdnets.asus.com/pub/ASUS/...UM_v2_web.pdf?model=TUF GAMING Z590-PLUS WIFI

 

[Ineocla]

No.
Read user manual of your motherboard.


https://dlcdnets.asus.com/pub/ASUS/mb/LGA1200/TUF_GAMING_Z590-PLUS_WIFI/E18030_TUF_GAMING_Z590-PLUS_WIFI_UM_v2_web.pdf?model=TUF GAMING Z590-PLUS WIFI

Oh well i stand corrected. So now at least i know there is a problem with the gpu but i still don't understand Why this one gpu specifically and not another

 

[mmp09]

What is the wattage rating of this and other GPU(that works) . I guess RX6800 itself draws 300W? Have you tried turning on the system with absolutely bare minimum parts, no HDD/no SSDs just one stick of RAM and the GPU in question. My guess is somehow this GPU is not getting enough power.

 

[Ineocla]

It's possible but i doubt it since the gpu worked perfectly fine for a few months before i swapped gpus. Also i put my config on both the bequiet et coolermaster psu calculators and they both seem to indicate 750w is sufficient

 

[Ineocla]

What is the wattage rating of this and other GPU(that works) . I guess RX6800 itself draws 300W? Have you tried turning on the system with absolutely bare minimum parts, no HDD/no SSDs just one stick of RAM and the GPU in question. My guess is somehow this GPU is not getting enough power.

As expected still nothing even after unplugging all my storage and removing one stick of ram. I even tried to unplug my case fans to make the power draw as low as possible

 

[Ineocla]

UPDATE : so i tried with a GeForce GTX 680 which is known to be working and none of the two pci slots could do somthing with it. The VGA error light was still on although the gpu fans were spinning this time. So now i only have two culprits right now. The psu and the motherboard. I'll try to see if i can test with a different psu so i can finally find what i should replace