Check if you must start your work and see if the 24-pin connector has all its pins.
Check if you must start your work and see if the 24-pin connector has all its pins.
Hello, Building a PC for the first time and maybe not choosing the simplest ITX configuration. Still, having the power supply and cables ready was attractive, along with the In Win B1 design. While I followed the manual and watched videos to connect everything, I noticed something unusual. The 24-pin connector appears to be missing one or more metal pins. Is this typical? When powering on, after pressing the ON button I see the front light up and the fans start, but the BIOS screen fails to appear and I can't use the ON switch to shut it down, so I have to unplug from the wall. I considered it might be an M.2 SSD since it doesn't sit flat horizontally during installation, even though the board seems to fit and lets the heat sink rest. However, I reinserted it on the motherboard's back and the startup problem remains. Here’s my configuration: AMD Ryzen 7 5700G 3.8 GHz, 8-core processor, Gigabyte B550I AORUS PRO AX Mini ITX AM4 board, TEAMGROUP T-Force Delta RGB case, 32 GB RAM (2 x 16 GB), Samsung 980 Pro 1 TB, M.2-2280 PCIe 4.0 X4 NVMe drive, housed in a 200 W power supply unit. I plan to bring a USB drive next week to update or flash the BIOS to F13, as the board says it needs this for CPU recognition. Yet it claims it can flash the BIOS without any CPU, RAM, or GPU installed. Shouldn’t the BIOS screen appear on my Dell device even if it hasn’t been updated yet? I’d appreciate any help you can offer. Thanks.
Absolutely typical. This pin is absent from every power supply I've tested, and the ATX pin layouts I've discovered always show it as N/C (no connection). No. The BIOS flashing method requires a precise setup: insert the flash drive in a specific manner, press the designated button on the motherboard to trigger the BIOS file read and write, and then the system remains inactive throughout. Just to clarify, using F13 and subsequent keys works, not just F13 alone. I’d upgrade directly to the newest BIOS instead of settling for the lowest supported version. A BIOS update should come first after confirming all power connections are correct. If you need a USB drive for BIOS updates, opt for the lowest capacity and slowest speeds available—higher capacities or faster drives can cause problems with certain BIOS Flashback features. Some boards are more demanding than others, but these older drives generally function reliably, even though my newer ones occasionally encounter issues. Unfortunately, I haven’t used Gigabyte’s latest BIOS Flashback setup, so I can’t confirm how sensitive they are.
The missing pin/wire was for -5v which is no longer used by modern computers. There's also a -12v wire which may as well be missing, as it's only used by serial ports (if your motherboard doesn't have headers for serial ports you can be sure that voltage isn't used) -5v was needed by very old memory sticks (before SDram) and by some logic chips up to maybe 386 time.