pc only boots with igpu, but not with installed gpu.

[roman_triller]

folks, i really need your help, because i'm a pc noob and hope to find some nice people who can help me to solve my issues.

 

i will reuse my old gpu from my old pc. on my old pc, the gpu works as intended without any issues. but when i build the gpu in my freshly built pc (all pc parts, except the gpu, are completely new bought), he simply won't boot. niente, nada on the screen. all coolers are spinning as they should. the strange thing is, that the pc boots completely normal when i remove the dedicated gpu and use the onboard gpu instead. in the beginning, the pc booted without issues, when the gpu was installed, but after a while the screen becomes black, so i have to push the reset button. this doesn't happen with removed gpu (when i used the igpu). but without any reason, the pc simply won't boot anymore with installed gpu.

 

what i did so far:

• updated bios to the newest version.
• disabled the igpu when the gpu is installed.
• changed pcie gen 4 to gen 3, even when all pc parts are for 4.0, even the riser cable.
• tested the riser cable if it's faulty, which is not the case.
• "tested" the gpu (it's the gpu from my old pc, which works there without issues.)

 

my built in hardware if needed:

cpu: amd ryzen 5 9600x
cpu cooler: thermalright axp90-53x full copper
motherboard: asrock b650i lightning wifi
memory: g-skill flare x5 32 gb (2x 16 gb)
storage: samsung 990 pro 2 tb
video card: gigabyte gaming oc 3060 ti
case: fractal design terra
power supply: corsair sf750 (2024)
case fan: arctic p12 slim

 

this is how it looks like when i press the power button:
 

[Whiro]

May sounds stupid but did u connect power from psu ? (Can’t see cos it’s dark pic ) 

Also u are connecting hdmi to the gpu directly not the mobo yes ? 

[roman_triller]

it doesn't sound stupid, it's a common mistake i know. but everything is connected as it should. hdmi cable from the screen to the gpu and not the motherboard. there are two pcie power cables (6 + 8) that are connected from the psu with the gpu's pcie slots.

 

when i'm home, i'll post some pictures of how everything is connected. i guess, that makes troubleshooting much easier.

[roman_triller]

@Whiro

 

is this picture helpful?

[Whiro]

On 11/12/2024 at 3:53 PM, roman_triller said:

@Whiro

 

is this picture helpful?

Wait not sure if I see correctly but ur gpu is on the other side of pc case but I don’t see raiser cable connected to the motherboard 

[Whiro]

[roman_triller]

Yes, it's because the GPU wasn't plugged in at this time.  

Short update: I just reseated my PSU, the motherboard and the GPU, unplugged and plugged every cable again. The PC boots now, even with the GPU plugged in, BUT after a while (approximately half an hour) a black screen appear randomly. “No Signal” appears on the screen, so I have to press the reset button to restart the system. That happens when I idle in the bios or when I boot into the OS and doing some work there. It doesn't matter. After idling in bios for about half an hour, the temperature of the CPU and motherboard looks like this. But I have the feeling that the pc parts are much warmer than stated here.