Prior to opening your case locate, but do not memorize, all of the screws you can find. If they happen to be of the Philips head variety, easily removed by using an applicable Philips screwdriver of the right size, try to select a screwdriver, flathead or otherwise, which seems sufficiently NOT suitable to remove the screws. The intention here is to improve chances of inflicting serious damage to connectors, expansion cards or other items adjacent to the screw by letting the screwdriver slip. Also, apply as much force as possible; bending the sheet metal of the case is a great measure of sufficient force, to maximize the possible damage. Also, turning the screws clockwise with excessive force is a good way to strip threads or, even better, break the head off completely, which will most likely require the purchase of a new case or the use of powertools to remove it.

Fig 1. The case panels and power supply secure fastened, this is not the proper way.
Furthermore it is absolutely essential to remove each and every screw within sight, especially the ones holding the powersupply and any heavy case fans mounted in your system. The effects of a powersupply falling inside the case are not to be underestimated; the same applies to the case fans. For maximum effect this should actually be attempted when the machine is still running, which will, with a little luck, cause the entire computer to short out and destroy some of its most vital and expensive parts. I reckon the effect the spinning blades of a large high rpm case fan can have on your fragile computer’s interior needs no elaboration. Now, when removing screws, don’t worry about them falling into the computer through open slots or other openings in the case, this is highly recommended. The screws not only can cause serious damage, they usually end up in places where you least want them, or cannot easily reach them, thus making you head out for the store for new ones. And there’s the added bonus of the sheer anxiety one feels when a screw is lost in the inside and cannot be found. Flipping the powerswitch can then be both a gratifying as well as an exciting undertaking, as recovery of the screw may destroy the computer.

Fig 2. All the screws removed and the power supply slowly falling into the PC' interior.
So far, we have found that just the removal of the case panels can result in one or more vital parts being utterly wrecked, which may well require a considerable investment to get the machine working again. Remounting the case panels back on should be done with care too, as I mentioned, you’re not to memorize the actual location of the screws, but rather screw them into any opening you see fit. Favorite locations include input/output connectors of sound- and videocards as well as voltage selectors for 110/240 volts operation. Also any holes which look like they have live parts, or electronic components, mounted right behind them are definitely prime candidates. Also having screws left over after the case has been re-attached is a big plus, as this will most likely result in components not being fastened properly.