Hey there, let's break down this issue and walk through some practical troubleshooting steps together!

First, let's recap what you shared: you took out your NVIDIA Quadro K620 to test another GPU, but when you put it back, the system started beeping, and you noticed one pin on the card is shorter than the rest—though the back side of the pins looks properly aligned.

Here are some things to check and try:

• Confirm the "short pin" is intentional: A lot of GPUs (including Quadro models) have intentionally shorter pins as part of their design—either for keying (to prevent wrong insertion) or specific power/signaling functions. Compare it to the other GPU you tested (if it's a similar form factor) or look up the official pinout specs for the Quadro K620 to make sure this isn't a damaged pin.
• Re-seat the GPU properly: Beeping sounds almost always point to loose hardware. Make sure the K620 is fully pushed into the PCIe slot until you hear both side clips click into place. If your model requires additional power (some low-profile K620s don't, but double-check), ensure the power connector is plugged in tightly.
• Clean the contact points: Dust or oxidation on the GPU's gold fingers or the PCIe slot can cause connection issues. Gently rub the gold fingers with a clean eraser (avoid touching contacts with bare hands), and use a soft brush to clear dust from the motherboard's slot.
• Reset your motherboard's CMOS: Swapping GPUs can sometimes leave residual BIOS settings that cause conflicts. Try clearing the CMOS (remove the motherboard battery for 30 seconds, then put it back) to reset to default settings, then re-install the K620.
• Test in a different PCIe slot: If your motherboard has multiple PCIe x16 slots, move the K620 to another one. This can rule out a faulty slot as the cause of the beeping.
• Check power supply stability: Make sure your PSU is providing consistent power. Try using a different power cable (if applicable) for the GPU, or confirm the PSU has enough wattage to support the K620.

If you notice specific details like how many beeps there are (different beep codes mean different issues), feel free to share that—it’ll help narrow things down further!

备注：内容来源于stack exchange，提问作者Popi