Opening and Closing The Computer Case
First of all, disconnect all of the monitor, keyboard, power cables (etc.) from your computer tower so that it is totally separated. Press the power button your tower just to burn off any remaining electricity in the power supply. You might see a light flash or hear then slight whirring of a fan for a split second.
Look at the back of the tower. Undo the screws at the opposite side of the connectors. This is usually the right hand side if you are looking from the back. This should allow you to slide off a side panel and give you access to the motherboard.
Some towers will require the entire casing to be removed in one go. These are horrible cases! You have to undo all or the screws and slide the case off. Sounds easy, but you wait until you try to get it back on!
Some cases have levers and doors to provide easy access. They're not as easy as they are supposed to be, but there are usually instructions on the case. It usually involves holding a lever down while you pull a door open. Patience is key here, don't go in forcing things open else you could break delicate clips meaning that you won't be able to close it properly when you're done.
With all types of cases, be careful! Most have sharp edges that will cut into your fingers. Yes, it's slightly uncomfortable, but these little cuts just want to bleed forever which is extremely annoying!
Now you have the case open be careful not to accidently pull any wires from their current locations. Guessing where they should go can cost you the motherboard! If you feel it will make things easier to remove some cables, make notes and / or, take a few photos before you get started, unless, of course, you are familliar with where they belong.
As you have the case open, you may as well take a bit of a look around to see if you can spot anything that has the potential to cause problems. A common potential issue is dust and dirt causing over heating.
Reconnect any wires that you have disconnected. Double check the 12v 4 pin power connector near the processor (easily forgotten) and any fans (especially the processor fan, VERY IMPORTANT!).
Have a check to see that no wires have come loose or unlcipped. Also (VERY IMPORTANT), make sure that no wires are crossing over the fans, or are likely to. Some insulation tape will help secure nuisance wires, but only use it to bundle wires together rather than stick them to casing as it will become loose.
Slowly slide the side panel back in place, being careful not to catch your fingers (I've done that too many times!) or catch any wires (done that too!). Watch as you slide to see where it should connect with the rest of the case. Being patient and observant here will save you time. If you have an all in one shell, just be extra careful and observant. It does get easier the more you do it, but not by much!
Connect everything back up. Before you power on, make sure you have access to the mains switch. Power on and listen for anything unusual. If you hear any unusual bleeping, scraping, clanging, banging, power off immediately! If you've had to power down, reopen the case and look for the cause of your problem. It's most likely a wire catching on a fan or a wire has become loose. If you've been careful, there should be no problems and, hopefully, the repair has been a success!
Look at the back of the tower. Undo the screws at the opposite side of the connectors. This is usually the right hand side if you are looking from the back. This should allow you to slide off a side panel and give you access to the motherboard.
Some towers will require the entire casing to be removed in one go. These are horrible cases! You have to undo all or the screws and slide the case off. Sounds easy, but you wait until you try to get it back on!
Some cases have levers and doors to provide easy access. They're not as easy as they are supposed to be, but there are usually instructions on the case. It usually involves holding a lever down while you pull a door open. Patience is key here, don't go in forcing things open else you could break delicate clips meaning that you won't be able to close it properly when you're done.
With all types of cases, be careful! Most have sharp edges that will cut into your fingers. Yes, it's slightly uncomfortable, but these little cuts just want to bleed forever which is extremely annoying!
Now you have the case open be careful not to accidently pull any wires from their current locations. Guessing where they should go can cost you the motherboard! If you feel it will make things easier to remove some cables, make notes and / or, take a few photos before you get started, unless, of course, you are familliar with where they belong.
As you have the case open, you may as well take a bit of a look around to see if you can spot anything that has the potential to cause problems. A common potential issue is dust and dirt causing over heating.
Reconnect any wires that you have disconnected. Double check the 12v 4 pin power connector near the processor (easily forgotten) and any fans (especially the processor fan, VERY IMPORTANT!).
Have a check to see that no wires have come loose or unlcipped. Also (VERY IMPORTANT), make sure that no wires are crossing over the fans, or are likely to. Some insulation tape will help secure nuisance wires, but only use it to bundle wires together rather than stick them to casing as it will become loose.
Slowly slide the side panel back in place, being careful not to catch your fingers (I've done that too many times!) or catch any wires (done that too!). Watch as you slide to see where it should connect with the rest of the case. Being patient and observant here will save you time. If you have an all in one shell, just be extra careful and observant. It does get easier the more you do it, but not by much!
Connect everything back up. Before you power on, make sure you have access to the mains switch. Power on and listen for anything unusual. If you hear any unusual bleeping, scraping, clanging, banging, power off immediately! If you've had to power down, reopen the case and look for the cause of your problem. It's most likely a wire catching on a fan or a wire has become loose. If you've been careful, there should be no problems and, hopefully, the repair has been a success!