Question Newly built PC won't turn on when graphics card is connected!

[sk80au]

Hi I just finished building a new PC but it won't turn on. I have the intel 109400f without iGPU and when I disconnect the graphics card the system turns on but I can't see anything on the screen because there isn't any iGPU to see what's happening there. As soon as I connect the graphics card system stops booting at all. As if there is a faulty PCIe slot. I tried with another PSU and graphics card and same thing happened.
Any ideas?

 

[VirtualLarry]

I have the intel 109400f

?

As soon as I connect the graphics card system stops booting at all. As if there is a faulty PCIe slot. I tried with another PSU and graphics card and same thing happened.
Any ideas?

Do you have all of the power cables properly connected? The 24-pin ATX connector to the front-most side of the mobo, the 4+4 pin connected to the upper-left side of the mobo into the 8-pin connector, and also, the 6 or 6+2 pin PCI-E power connector to the end of the GPU? Those leads should be labeled "PCI-E" coming from the PSU.

 

[sk80au]

Yes they're all plugged in
correctly.

 

[VirtualLarry]

Do you have a "Beeper" plugged into the mobo "SPKR" 4-pin header (two outer pins), and did you remember to connect your monitor to the GPU's outputs, and not the mobo? I helped a friend build a PC (guided him, he did the work). He did it all correctly, but I misunderstood what he was asking, and he had the HDMI cable plugged into the mobo's outputs (this was an AM4 Ryzen CPU rig, so no iGPU support), instead of the RX 570's HDMI output, so of course, he didn't see anything when it tried to boot. But we had the speaker hooked up, and could hear it beep when it booted. Took me a day of thinking about it to figure out what was going on, he stopped wanted to trouble-shoot after it didn't boot first time.

You could always "Bread-board" the system. Place the mobo (remove from case, if need be), onto the cardboard box, connect CPU, RAM, power cables, GPU, GPU power cables, and power on the PSU switch on the back, then use a screwdriver to short the PWR_SW jumper on the front-panel header. See if the PSU and CPU cooler fan spins, if you have a beeper connected, see if it gives you beep error codes, or if you have "Diag LEDs", what they show you.

 

[sk80au]

I don't have the beeper but it's not going to help me as the PC won't turn on at all. i mean the CPU fan won't work

 

[UsandThem]

I don't have the beeper but it's not going to help me as the PC won't turn on at all. i mean the CPU fan won't work

I thought it would start if you didn't have the GPU installed? Have you tried the GPU in a different slot?

Please list all of your hardware so we can see what you have. Another thing, there is no "109400f". You either have an i9-10900f or an i5-10400f.

 

[sk80au]

Yes it'll turn on when gpu is unplugged. Sorry the CPU is i5 10400f.

Motherboard: Asrock b460m-itx
Memory: 2x8GB DDR4 2666MHz
PSU: Silverstone 650W Bronze full modular

 

[UsandThem]

Of course it is a dreaded ITX motherboard with only one full PCIe slot.

I'd say if you're sure you have made sure you've done all the power connections properly (the main, CPU, and possibly on the video card), and you've tried two different power supplies and two video cards, the issue will likely be with the CPU or the motherboard.

Probably at this point, you probably should try another motherboard as the next step, since CPUs are a lot less likely be defective out the box.

 

[sk80au]

If I connect an old graphics card that doesn't require additional 6pin or 8pin power then the system starts.
It posts into BIOS. Strange!

 

[sk80au]

I fixed the issue by updating the BIOS.
First plugged a very old graphics card to load into BIOS then updated the BIOS.
Shut down the system and disconnect ed the power cord from PSU and then installed the new graphics card and it booted fine this time.