To show off the Mini Q PC-V354's capabilities, we originally planned to install an insane amount of high-end hardware. The list included Asus' Maximus II Gene motherboard with 12GB of DDR3 memory, a Core i7 980X Extreme Edition, and the monstrous Radeon HD 5970.
Realizing that was probably overkill, we decided to try something a bit more feasible, opting for the Gigabyte AM3 mATX board with the new Phenom II X6 1075T processor, and one Gigabyte GeForce GTX 460 graphics card.
The same procedure is followed no matter what you plan to install. You'll have to remove both side panels exposing the internals and detaching the motherboard tray. With the right panel/motherboard tray removed, you can easily install the motherboard, RAM, CPU and cooler.
As usual, you'll want to install the I/O shield before stuffing the motherboard back in, but if you forget, the board doesn't need to be unscrewed as it is separate from the I/O bracket.
Since we planned to install a longer graphics card after testing the modest hardware, we decided to leave the bottom 3.5" cage empty, with a pair of Samsung 2TB hard drives in the top cage. We found it easiest to remove the cage to install the drives and cables.
It's best to install expansion cards before the power supply, but it's still possible to squeeze one in beside the PSU if necessary. We installed the GeForce GTX 460 1GB without removing the lower 3.5" hard drive cage and a second card would have fit as well.
The Thermaltake Toughpower XT 675W was secured by four thumbscrews and fit well, but we wish there was a little more wiggle room. Since it's a tight squeeze, our unit was pretty scratched up. It's also worth noting the Mini Q PC-V354 has no side ventilation for the power supply so the 120mm fan in our unit has a tough job of keeping things cool.
You might have somewhat limited options for a CPU cooler as it sits right below the PSU. We mounted the Cooler Master Hyper TX3 vertically under the power supply, but depending on your motherboard's socket placement, you could get away with mounting much larger CPU coolers horizontally.
As expected, by removing the lower 3.5" hard drive cage we were able to install the Radeon HD 5970 without a problem. At 31cm, it's the longest video card we know of and squeezing it in such a small chassis is truly impressive.