How to Build a Small Gaming PC
7. Route the Power
Now is a good time to route some power‑supply cables. Bring the 8-pin and 24-pin ATX power cables and one PCIe cable around the front of the PSU to the right side of the case. Route a SATA power cable along the left side to the hard drive bays, connect one port to the hard drive, then terminate it at the SSD, leaving the middle port for a future second drive (image H). Route the other SATA power cable along the bottom of the case, up the front panel, and into the routing hole just above the optical drive. Pop the top fan filter off and route the cable above the optical drive and plug it in (image I). Route SATA data cables from the blue 6Gb/s SATA ports to the SSD and HDD, and route one from a red 3Gb/s port to the optical drive.

Image H

Image I
8. More Routing
Disconnect the HD_Audio cable from the side panel and connect the motherboard end to the mobo, as the port will be impossible to access once the GPU is in place. Run the 24-pin motherboard power cable through the front of the PSU casing and into the port on the motherboard. Run the 8-pin through the cutout toward the rear of the casing (image J) and plug it in. At this point you can reattach the top hard drive cage if you want; I’ve left it out to improve airflow.

Image J
9. Attach Front-Panel Connectors
Plug the USB 3.0 header into its place below the radiator (image K). Connect the front 12cm fan to a 3-pin-to-Molex adapter and connect that to one of the Molex adapters. Re‑attach the other end of the HD_audio cable to the left side cover (image L) and put the cover back on the side, pulling the front-panel headers through toward the GPU slot and plugging them in.

Image K

Image L
10. Install the GPU
Unscrew the expansion‑slot cover plate and the expansion‑ slot covers, and remove them. Install the GPU, making sure the 8-pin ATX power cable can still reach its plug. Replace the cover plate and secure both it and the GPU with the three thumbscrews (image M). Run the PCIe power cable through the same hole as the ATX power cable and plug both 6-pin plugs into the GPU. Secure the PSU plate to the chassis with its four thumbscrews, double-check your wiring, and close the case back up. Screw the Wi-Fi antennae into their posts on the I/O ports.

Image M