PC not POSTing after inserting 2nd GPU

[WalterTheModeler]

Hey there kind people! I have 2 GPUs - RTX 3060 and a GTX 980 Ti, both of them work if they are the only GPU in the system in either of the PCI-e slots. However, if they are plugged in at the same time, after powering on the pc it doesn't get to the BIOS screen and motherboard shows the "boot" error light.

 

Now they did previously work in that configuration (both GPUs at the same time), I only ran into this problem when I installed a new m.2 drive in my pc. Next time I turned it on, it stopped POSTing. Later I even disconnected ALL the drives from the system, no m.2 and sata drives were left connected, yet the pc still didn't post until the 2nd GPU was removed.

 

I'm thinking this could be a power supply issue as I'm running a Corsair 750w power supply. However before I purchase a new (1500w) PSU I want to have some confidence that it will actually solve the issue.

 

My PC specs are:

Ryzen 5950x

32 GB RAM

ROG Strix B450-F Gaming

Corsair RM750x PSU

 

GPUs (can only use one at the time because of this):

RTX 3060 EVGA

GTX 980 Ti  Gigabyte Xtreme

 

Drives:

1TB WD nvme m.2 ssd

256GB kingston ssd

2TB Seagate HDD

4TB Seagate HDD

[Portednormal]

sounds like a power issue but thats weird if it was working before adding the ssd.

could have fried the board? i was working on a older pc today with an AMD FX series setup in it and everything was fine untill i unplugged it and took the graphics card out to clean it and BOOM either the CPU or the MB died. It powers on for a split second then shuts off right away so if its doing the same for you start there if you have an extra board laying around to test

[WalterTheModeler]

Thanks for sharing! I have an extra board, but it doesn't have 2 PCI-e slots. The thing is, the pc works, if I only put one GPU in it (in either of PCI-e slots), so the board must be working just fine. But I do need both of the GPUs in the system as my work requires as many GPUs as I can slot in there.

 

It's really weird stuff