If you have a big honkin’ desktop computer and a little bitty desk, you might be tempted to simply place your computer on the floor next to it or underneath it. Please don’t. That goes double if your desk is in a carpeted room. It’s bad. How? Why? Allow me to briefly explain.
Your desktop generates quite a lot of heat from its internal components, especially if it has a powerful CPU and graphics card. In order to cool it down, it circulates air in and out, very much like a car engine. Because your PC isn’t constantly moving at 60 miles an hour, it needs to do so with a series of small fans. The circulation fans are what make the “whir” noise when your computer turns on.
If you place your PC on a carpeted floor, then the intake or exhaust fans that face down are obscured. Not every computer uses bottom-mounted fans, but many do, especially for the critical power supply component (the thing that you plug that thick power cable into). Blocking intake or exhaust will mean your computer runs hotter, and therefore, with less efficiency.
Even if you don’t have carpet, you want to keep your computer away from dust as much as possible, and your floor has a ton of dust. Keeping it down there means that you’ll have to clean it out more frequently to keep it running well.
If you can’t fit your PC on your desk or you simply want the space on top, you can get a small end table to place it on. A little $20 MDF table will do just fine, if it can handle the weight and you’re not concerned with aesthetics. As long as your PC is flush with the surface, with the legs allowing airflow underneath, it’s effective.
If you’d like something a little more discrete or you need your desktop PC to move with a standing desk, then consider mounting it underneath the desk with a “CPU holder.” (That’s a misnomer, it holds the entire machine and not the CPU, but this office accessory doesn’t have a more widely-accepted general term.) You’ll need to ensure it’s safely attached, but once it is, it makes an excellent and cozy home for your computer.
CPU Holder Under Desk Mount - Adjustable Wall PC Mount with 360° Swivel, Heavy Duty Computer Tower Holder Holds up to 22lbs by HUANUO
This tool hides your big desktop PC underneath your desk, so it's off the floor but out of the way.