A friend gave me a Mini-ITX computer his father was no longer using. It was a basic desktop mainly used for office tasks and Skypeing. It was in an Antec ISK310-150 case.
I decided to upgrade it so it could play Neverwinter Nights Diamond and to see if I could do that in such a tiny case. All I really needed to do was add a video card capable of 3D rendering. The only nVidia card that would fit inside the case turned out to be a low profile GT 1030. It had a ASUS Z97I-Plus motherboard and a dusty Antec 150W power supply with a lot of miles on it. In the end, the only parts I kept were the case, motherboard, and one hard drive.
I thought adding a video card and perhaps some other peripherals might overload that aged power supply. I like 80+Gold efficiency and the Seasonic brand; the SSP-300SUG is the only one that would fit. Unfortunately, none of the screw holes would line up and the female power plug is on the back plate of the case. I had to splice a male plug into the interior to fit into the power supply, and anchor the power supply to the bottom of the case with stick-on Velcro. The wiring harness that came with the Seasonic power supply was much too long (thus hindering air flow), didn't have all the necessary plugs, and had a superfluous floppy drive plug. I bought Molex and ATX power supply pin removal tools. I changed the two 4-pin motherboard power plugs to a single 8-pin plug. I shortened the SATA power cable and added the necessary slimline plug for the optical drive. I added color coded sleeves to those and to the Molex power cable. I don't have an ATX pin crimper so I made do with needle-nose pliers and then soldered the wires to the pins.
I wanted CL7 RAM rather than the CL11 that came in it. Just because.... There was an empty mini-PCIe slot that needed a WiFi/Bluetooth card for the same reason.
The computer came with one hard drive and I scavenged the other from another project. I used a fix-it CD with the Western Digital utilities to zero both drives and then performed deep scans to make sure they were OK. I've installed Devuan Linux on the first half of the 1TB drive. I'll install Windows 10 Pro on the 500GB drive. I'll create a shared partition that each O/S can see on the second half of the 1TB drive. When the price of SSDs comes down a bit from where it was on Cyber Monday last year, I'll replace the two spinning disk drives with Samsung 860 EVOs.
Due to the recent vulnerabilities to hyperthreading CPUs and the fact that I installed buggy-as-a-bait-store Windows, I upgraded the 2-core-4-thread i3 that came with the computer to a 4-core i5. There was a massive aluminum CPU heat sink which looked like it impeded air flow through the case. I tried to replace it with a Zalman CNPS8900 Quiet, but it wouldn't fit, so I used a Zalman CNPS2X. The CPU temperature rose by 5 degrees C or so from the aluminum cooler, but there is now clearance between the CPU heatsink and the RAM sticks.
All my other computers have Blu-Ray burners. This one will be no exception.
I like plenty of screen real estate without overtaxing my peripheral vision, thus the Samsung monitor.
I carved out some of the styrofoam in the box the monitor came in and now the keyboard, mouse, cables, and other peripherals will fit. The idea is when I travel to my friend's place, I can carry along a compact computer and a monitor the size I'm used to for our LAN games.
It will never be blazing fast and it won't play any bleeding edge games, but it will serve the purpose and it's been a satisfying and entertaining project. The CPU and RAM were used. Several parts were open-box. The fans, heat sinks, power supply, and GPU are new. If I had used all new parts, I'm sure my costs would have more than doubled, and perhaps tripled.