[SOLVED] PC don't boot after connecting 2 gpus

So guys, configured, everything the system reconizes the gpu i wanna pass to vfio but i can’t boot when i connect the cables for both gpus, system freezes and hang up on “Starting Dracut pre-udev hook” and don’t go beyond that. If i leave only the Igpu that is configured for host, i can boot no problems, but if i try to leave only the pcie gpu card, the same problem happens

I followed PCI passthrough via OVMF - ArchWiki

My files

vfio-pci

options vfio-pci ids=1002:73df,1002:ab28

(didn’t enable softdep since i’m using dracut force, but no matter if i do, the same problem happens)

10-vio.conf

force_drivers+=" vfio_pci vfio vfio_iommu_type1 "

same as the wiki and i’m out of ideas

My os is garuda
Igpu from ryzen 7600x

Gpu Amd 6700XT

Additional Context: System is giving video for both outputs only if they’re connected from boot. If i connect after booting, it’s only a blackscreen

And looking at it again First output Dvi (which is the Igpu Host): Stuck on starting dracut pre-udev hook

Second output Hdmi (Gpu Vfio) final 2 lines: Reached target Graphical interface Finished Clean up modules from old kernels

And then system hangs indefinitely

Welcome PhtRonin…gotta ask it, got the power to do two cards?

check to see if you have peg1 mode disabled or set to something other than the pci-e 1 in bios.
(your first gpu slot)…
if you have an igpu then it may be set as the default which would cause the black screen on the other cards output.

then theres power… you got enough?. 2 gpus 1 cpu your looking at 440w ish for the gpu’s 120 for the cpu another 100 for motherboard and drives…
so if your rocking a little light in the ass psu 800w or less, it might be the issue.

lastly you cant boot the cards after boot (your plugging in the power to the gpu after the system starts?)… the bios wont see the gpu’s if they have no power at boot, so wont know to load them into the the hardware stack.

Have you checked if the system itself is hung, or just display dead?

Like, tried to ssh in from another box?

Thanks, yes i have a psu of 600w i believe it shoud be enough

This one i didn’t understand, i actually set up to boot directly on igpu so this is the problem ? I should leave it for pcie then ?

I have a 600w psu, but i did the math: gpu consumes 230w, cpu 130w,motherboard 60w, it should be enough, unless it consumes more when the two is enabled ? If this was a psu issue then i wouldn’t be able to boot even with only my GPU right ?

Yeah it makes sense

i used it frozen as a manner of speech, i can restart with ctrl+alt+del just doesn’t go beyond that, but computer keeps working normally

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The following are recommended minimum requirements for installation of AMD Radeon™ RX 6700 XT graphics cards: • PC with at least one PCI-Express x16 graphics slot available on the motherboard. Minimum 650W system power supply • Minimum of 8 GB of system memory, 16GB is recommended.

Looked it up that is probably excessive and at full bore but even if it’s using half of that it would add up with your cpu and the rest of your parts

Yes i’ve seen that before i bought it, but i checked for reviews on power consumption and noticed my psu would support even if amd doesn’t recommend it. I already tested it playing heavy games and the system didn’t shutdown.

I’m reluctant because psu is not cheap and i don’t know if it will fix the issue. But i see the point, even if is not the case it will give more margin for the system

But oh well, gonna try on Fedora for testing purposes. If it doesn’t work then i will buy another psu

Yeah continued to look and you are pushing the limit too much on the power supply most likely

You’re right gonna buy it regardless just to give more room

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Just stay with one so you don’t starve your parts trying to make it work till the new one comes in

yeah you have enough psu to power one card.
doesnt matter that your math says your scraping by.
230w+230w=460 + 130w cpu your already at 600
and you need another 100 to power the motherboard.

basically you will be able to power it all up. but as soon as you use it it will fall over.
and if the psu is a single high volt rail or on the cheaper end without good over/undervolt protection.
its likely you will take other components when the psu goes.

so for now limit yourself to 1 gpu…
and to do that
plug 1 in to the top most pci-e slot.
go into bios and find first output/display/peg mode. (you will have to tell us what motherboard you have if you want the exact location in bios),
but this setting will turn off the igpu and switch your pc to the dedicated card…
connect the vga/hdmi/dp cable into the back of the gpu… not the motherboard.

reboot the machine and the gpu should show up and boot with a display.

Ok explain me this why 230 two times ? This passthrough is not for only the guest to use the gpu ? Consumption would be the same in my understanding
230w gpu maximum tdp, 130w cpu maximum tdp, 60 w motherboard, and room for other stuff
but yes psu have failsafe stuff too

Also i already did a test on fedora and under 20 minutes i got it working. This is not psu related: i only followed this guide GPU Passthrough Fedora · GitHub
and removed vfio_virqfd from dracut conf since is not needed anymore.

Once i rebooted to Garuda, the same problem again

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your running passthrough.
you want enough psu to cover your entire build that means both gpu’s
and at the very minimum you want 200w overhead on a single gpu build.

im just spitballing motherboard watage also as i dont know how many ssd/nvme/hdd’s.
audio or other addin cards. so i budgeted for 100w. and thats still an underestimate depending on ram and other addin cards you might have.

still. even at 600w your tight for 1 card never mind 2.

that sounds like garuda has a problem with your gpu drivers.
either your on the wrong kernal for the gpu, or the drivers might need updating

I understand that, but only one gpu consumes 230w the other is the one from cpu and i think 130w maximum is when you’re already using with igpu, when using PCIE GPU consumption from cpu should be less (talking about single card use here) but now i need to check this
My config:
Ryzen 5 7600x
Amd Rx 6700xt
Gigabyte b650m ds3h
1 SSD and 1 HD 7200rpm
One pci card for usb 3
3 cooler fan corsair af120

But yeah, not running with a lot of room and i agree i should be getting at least one with 700w.

Ok
I was thinking maybe i gonna check if can do similary to that guide and see if it works, but if not gonna check kernel or driver, but the driver is already the last one

with ONE gpu and no pci e usb card your at 479 watts so only 121 watts left for your second gpu + whatever else and you need headroom for power spikes. remember if the gpus power spikes up for a micro second its not counted on a lot of graphs but the psu still needs to be able to deliver that without over current protection activating. gamers nexus did a good video on this https://www.youtube.com/watch?v=wnRyyCsuHFQ

now you may ALSO have a second or third problem going on but power is definitely one of your problems

Part List - AMD Ryzen 5 7600X, Radeon RX 6700 XT - PCPartPicker they do the power math for you. some of the parts like do you have a water cooler? will change the numbers throw in your own parts.

Yes my system have water cooler, i wasn’t brave enough to use air cooler on this specific cpu, is hot as fuck lmao

Anyways guys, managed to pinpoint the problem. This is a btfrs issue, reinstalled fedora using this partition (which is also the same of garuda) and the same problem happened. Don’t know why btrfs cannot boot after binding vfio to gpu, if anyone else stumble on this same problem, this is the issue.

Now on my way to browse a psu 80 plus yada yada haha

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I hate to be that person but your computer will be starved for power even if it’s not showing it and was fixed. That can be worse for parts then overclocking…I wouldn’t use it much or personally any at all till a new PSU gets installed just as a heads up.

I would leave it till that time of install to ensure your parts don’t get power starved and have issues later in its life because of it

About this site, i used this one Power Supply Calculator - PSU Calculator | OuterVision

posted my entire config there, (except for the pci usb 3 and water cooler that i didnt find, but consumption is low so i put a similar) this was the result AMD Ryzen 5 7600X AMD Radeon RX 6700 XT - PSU Calculator - Build 7F8Xgk

And their recommendation was actually a 550w psu lmao