Many modern cases ship with standoffs already installed on the motherboard tray, while others include them in a baggie and leave it up to you to place them where they need to go. (Image credit: Wikimedia via Petteri Aimonen) Make sure you've installed enough standoffs. These are labeled as “PCI-E” on the corresponding PSU connector.įinally, make sure all of the cables are firmly plugged into where they belong, both on the component side and on the PSU side when using a modular PSU. If you're packing a seriously powerful GPU, then you may need up to three 8-pin connectors. Separate from the motherboard, your graphics cards is going to need at least one power cable as well (there are exceptions, but they're niche), either one or two 6-pin or 8-pin connectors are common these days. Also be sure that you’ve plugged the appropriate PSU cables to your motherboard’s 4-pin or 8-pin CPU connector. On most modern PSUs, the four extra pins detach from the main connector. Some motherboards have a 20-pin connector.
If your PC isn’t booting, double check that the main 24-pin ATX cable is plugged into your motherboard.
It’s especially easy to overlook a critical cable on a fully modular PSU. Depending on your specific parts, you could be looking at three or more power cables extending from your power supply that need to be plugged in, and if one of those is missing, your system will just stare at you blankly when attempting to fire it up.
Your motherboard needs power, and so does your processor and graphics card. Routing the ATX 12V cable can be tricky, just make sure it's properly connected once you're done.