Question Problems with Multi GPU setup ?

[CosmicEgg_]

Hi guys,

I'm currently trying to setup a PC with both a GTX 1080 and an RTX 3090 Ti but i'm struggling to get it to work.

I tried many things but the current result is the 1080 booting with a code error 43 in device manager but work after a disabled enable and the 3090 Ti gets a code 45 and doesn't work at all.
Best I got was the 1080 working perfectly and the 3090 Ti showing up with no error but displaying nothing.

I can provide more informations on what I already tried and the result, I just don't that here it will be insanely long but I tried differents drivers, Windows reinstall, checked PSU, monitor and motherboard connections, etc.

Does someone have any ideas ?

 

[COLGeek]

What are the complete specs for this system? We need to know the make and model of each installed component. Details matter.

 

[CosmicEgg_]

Yeah sorry I forgot these, my bad.

-ryzen 7 5800x
-asus x570 e gaming
-32go 4x8 ddr4 3600mhz
-asus 1080 o8g
-nvidia 3090ti fe
-corsair 850w (main psu)
-generic 650w (psu for the 1080 only)
-2 m.2 nvme
-win 10 (up to date)

 

[QyInvoLing]

It's difficult to use two different gen cards made by the same manufacturer. Why do you do that?

 

[CosmicEgg_]

It's difficult to use two different gen cards made by the same manufacturer. Why do you do that?

Well because I have multiples monitors and I have a useless 1080 otherwise. Why would it be hard ? Some people seem to just plug the cards and it's working

 

[COLGeek]

How are you sending the power on signal to the second PSU?

Well because I have multiples monitors and I have a useless 1080 otherwise. Why would it be hard ? Some people seem to just plug the cards and it's working

Your newer GPU can easily handle more than one monitor. Sell the older one, or keep as a backup. You really don't need two GPUs.

 

[CosmicEgg_]

How are you sending the power on signal to the second PSU?


Your newer GPU can easily handle more than one monitor. Sell the older one, or keep as a backup. You really don't need two GPUs.

Wire on the 2 pins of the 24pins. I just turn on this psu before the other and then hit the power button.

I know this GPU can handle more than 1 monitor but for some reasons I might end up with 5 monitors which this GPU can't handle. Even if it this useless I really want to be able to use the 1080

 

[COLGeek]

I suspect the drivers are creating a ton of conflicts given the different hardware generations, each fighting to be the primary device and then failing due to driver conflicts.

You could try using DDU to remove ALL Nvidia drivers. Then install the 3090Ti (only it) and its drivers. If, after restart, everything is working. Install the 1080. No drivers. See if Windows auto-installs any drivers.