System fails to power on despite GPU installation
System fails to power on despite GPU installation
PC fails to boot without the GPU. With it installed, only RAM lights up while fans remain inactive. Without the GPU, all components spin and lights activate. However, 3900x lacks an integrated GPU—hard to determine the issue. I've tested various GPUs and power supplies. System specs: CPU AMD Ryzen 3900x, M.2 B550 Aorus Elite, 16GB RAM, 3600MHz Corsair LPX, GPU options MSI 6900XT or MSI 1070, PSU ST1200-PTS or BeQuiet 600W.
Ensure you're connecting through the GPU's display output. Have you checked the other PCIe ports on the motherboard? Why are you pairing an SFX-L with an ATX case? The 600W rating seems low for a 6900 XT, but the 1070 should handle it. Are you using a PCIe riser or extension?
I have tried all x16 slots with the same result: No fans spinning when GPU is installed. I havent used a riser cable. GPU directly slotted in all x16 slots. I tried both DP and HDMI on both cards. Since my cpu doesnt have iGPU there is no use trying on my mobo. I used the 600w just because I had that laying around without having to disassemble another rig. Just to try to get into bios.
I have tried all x16 slots with the same result: No fans spinning when GPU is installed. I havent used a riser cable. GPU directly slotted in all x16 slots. I tried both DP and HDMI on both cards. Since my cpu doesnt have iGPU there is no use trying on my mobo. I used the 600w just because I had that laying around without having to disassemble another rig. Just to try to get into bios.
It seems the problem might lie with the motherboard, CPU, or RAM rather than the PCIe bus or graphics cards. Based on my experience, Ryzen 5000 models before the G-series require a VGA adapter to boot, so inconsistent POST behavior across different cards suggests another issue. Without an integrated GPU, the CPU will need a discrete one. At this stage, verify RAM and CPU condition, check for damaged or misaligned pins, and test all possible DIMM configurations.
Are you connecting the cables that came with the power supply for the card? If not, that might be the problem—the cables are designed only for those supplies. If it’s not receiving power, you’re likely at fault. If you are using them, check the pins inside to confirm they aren’t pressed against anything or creating bad contacts. Also, make sure there’s one HDMI cable connected to the back of the GPU you’re using; this is usually clear from the setup.