Installing 3080 prevents booting

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3080 arrived yesterday, swapping it out for a 1070 which I sold last month. The system boots perfectly without the GPU installed, it also boots if the 3080 is installed but I change video output to the onboard CPU graphics - but then 3080 does not show in task manager or device manager. My brother has an identical 3080 and when I plug it in the exact same thing happens.

Both 8 pins are connected, its seated properly, tried display port and HDMI on the GPU. Tried without storage installed, rebuilt the system 20 odd times, new PSU is 850w. It was assembled in the case, but is now spread across the arm of a sofa - and I can still boot without GPU installed. I thought the pcie slot was broken, but if I set video output to auto and plug the display port into the motherboard it beeps at me to say graphics card error, whereas when I plug the display port into the graphics card the machine begins to boot, sends the successful boot beep code, then about 20s later sends out the failed to boot beeps - nothing is ever shown on the screen. So I'm guessing the motherboard can see it in the slot but is refusing to play ball.

My motherboard is an old lenovo from a thinkcentre but is x16 slot so I don't think it matters, I'm running an old intel 4th gen or something but I never had problems with my 1070. I've updated bios, tried using ddu, tried throwing it at a wall and tried throwing myself at a wall. Still didnt work.

Any ideas?

I have a new motherboard, cpu and ram coming as I upgraded the whole PC, but they don't come until tomorrow and I'm impatient... thankkss

Pics: gpu pcb is almost as big as mobo
https://ibb.co/BC8f7Mz - top half mobo
https://ibb.co/NypCXxv - underside - ik the slots that can be seen are pci, but the GPU is plugged into a 16x pcie.

 

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There is a VBIOS update for the TUF card you have, stick the card in a PC that allows it to boot then go to asus support page and flash the VBIOS and make sure to do it on both VBIOS, the TUF has two VBIOS so flash first one and then restart to make sure it worked and then shut down set VBIOS 2 and flash again.

Then try the card in your pc and should now hopefully work. Known issue with booting with the original VBIOS on many of the 3080 and 3090 cards until you update it.


https://www.asus.com/us/Graphics-Cards/TUF-RTX3080-O10G-GAMING/HelpDesk_BIOS/


Make sure to search support for the right version of your card, if an OC model or not. Above is a link to show you what I mean about being a VBIOS update. Do the update on a machine that allows the card to work, your brothers and if he has same card too, his will need doing too.


If it doesn't work after that, it means your motherboard BIOS is out of date and you may need to contact the board maker for an update they may have in the background and not on their site to fix the issue, but they may not too if it's a really old board.

That sounds like a good plan, I’ll go and stick it in my brothers PC and update them both. I’ll also send off an email to Lenovo to see what they say, I am currently on the most up to date bios version available. Thanks

 

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Why do you want to use onboard graphics when you have a 3080 installed ?? Its probably a limitation of the bios/motherboard but just why ? Doesnt make sense.

I'm not, I was wondering if the gpu was just not outputting to its ports so I set to integrated graphics so I could get into windows with the GPU plugged in to see if windows could see a device in the pcie slot. My intention is to have the gpu as video out once its functioning

 

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After sticking both 3080's in my brothers PC and feeling like a god, I borrowed my old 1070 off my mate and stuck it in my machine - it no longer works. 100% a mobo bios issue or maybe dust in the slot. Is there a way to revert back to a bios version where it still worked?