Well, I will give it a go and see where we end up.
One caveat - unless this is a Packard Bell, or Compaq Presario, chances are your case will be layed out in a similar manner as described below. If you have one of these two types of systems, it is possible you will have a very different layout, and may encounter many "screwless" options and snaps, plugs and retainers that hold the components in place.
Before starting, unplug the PC, and remove all cords (most are color coded) or mark them so you know where they go. Most are size or color independent, so it is kind of hard to get them in the wrong slots. USB plugs usually do not matter which slot they came from. Once the power cord is unplugged, turn the front switch on, as if you were trying to start the machine - this will discharge the capacitors in the PSU, and help eliminate excess static charges.
1.) On the backside of the PC, unscrew two (or three) screws on the right side (looking at the backside of the PC - left side if looking from the front) of the case. This should allow the side of the case to slide backwards and then be removed completely. Be sure to try and "ground" yourself by touching the metal structure of the case once the side door comes off. This eliminates any excess static charges you may have, and helps prevent damage to some of the smaller somponents that can be very susceptible to static charge.
2.) It is easiest to lay the case on its side, so you are looking down into it. There will be a few cards plugged into the motherboard that will have their external connectors sticking out the backside of the case. These will have a single screw in the top of the bracket that holds them to the case (unless you have one of those goofy types that uses a locking bracket to keep things in place - report back if there isnt a single screw in each card). Unscrew each screw, unplug the card by lfting straight up. They can be in there a bit tight, and may require a bit of force to remove them. Sometimes gently putting pressure on one side of the card, away from the backside of the case to dislodge it will help. Even wiggling sometimes helps remove these. They are pretty durable, so unless you use excessive force, these will lift straight out pretty easily with little fear of damage. You will most likely have a modem or network card (if on broadband) and possibly a sound card, and a video card. If you have an antiquated scanner or other external device, it is possible you have an older driver card that needs to come out as well. Be sure to note which slots these devices come out of, as they will need to go back into the same slots they came out of. These can be easy to mix up, and some slots are similar in design to others - but many newer components have different slot architectures. Also, there may be some cords running to other internal devices coming out of these cards 9particularly sound cards). Make note of where they plug in, and any oreintation they may have (certain colored wires facing certain directions). You may need to unplug these to get the card out of your way.
The only thing that you should leave will be the video card. It will most likely be the top most card (when the PC is standing up) and will be where the monitor cord plugs in. It is possible that many of these components are built into your motherboard, and you may not have any cards in these slots. This istypical on newer PC's (last 5 - 8 years). If your PC is considerably older though, you will most likely have a few cards there.
3.) Look at the front of the case, and see where any and all drives are located. Chances are you only see the CD-ROM and floppy drive. Any Hard Drives will be hidden from view from the outside of the case, and these are usually mounted below the floppy drive. Follow their cables down to the motherboard. Chances are you might have two of these on the same cord. The cords are flat, wide (usually gray) ribbon cables. These will plug in with big rectangular connectors. The power cords are small, squarish, and have multiple colors on them (red yellow and black usually). These go to the Power Supply Unit (PSU). Depending on the age of your computer, be sure to note that there is a red stripe on one side of the ribbon cable. It is actually one of the 40 wires that is colored red, or has some red marking on it. This red stripe runs the entire length of the cable, and tends to twist as it is routed through the components. It goes on the board in one particular direction. Most PC's within the last 10 years or so have a "keyed" plug and keyed outlet on the motherboard, but there are some that are not keyed (especially the older ones). If you look closely at the motherboard, you will see a small number "1" printed near the end of the socket where the red stripe goes. These can be hard to see - so it is easier to pay attention which way the cable is oriented, and which direction the red stripe is facing. This will only be necassary for when you replug the cord back in. If the plug and motherboard are keyed, there is no fear that you will insert it incorrectly (there will be a small square "bump" on one side of the cable, and small square notch or slot in the socket on the motherboard).
Take note of each of the ribbon cables which way their red stripe is facing. If space or tangles become an issue, and you have to unplug the cable from one of the drives, be sure you have easy access to replug the cable in (or you may have to take the drive out of the case to plug it back in). Or sometimes those cables work loose on drives, and you find the other end laying in the bottom of the case wondering how it got there. If this happens, don't panic, the red stripe 99% of the time faces the small power plug on the drive. Post back if you have to remove the plug from the drive or the drive from the PC (assuming you have access to another computer). You can bend one of the pins on the drive if the cable is not lined up correctly, and sometimes removing the drive is the easiest way to ensure this doesn't happen. So try not to unplug the cable from the drive unless you have no choice. And if you do have to unplug it, try to be sure to pick a drive that is easy to plug back in.
4.) Now, the only thing you should have left in your case that is still conencted to the motherboard is the CPU (kind of squarish, sort of tall with a fan mounted on top of it - or a card looking device that has some rather large fans or shrouds mounted on it. It is located in a seperate place from the periperal cards that stick out of the back of the case); the memory (long rectanular chips plugged into the board, standing up off the board like the peripheral cards were. Memory is usually located right next to the CPU)
as seen here The CPU has a round cooler in this case, the thing right above the gold anodized heat sink, and the two memory sticks are seen at the bottom of the picture - the green ones with all the chips on them). The only other thing left attached to the motherboard should be the Video card - unless it is integrated (the monitor will plug in right near the mouse and keyboard, and you will see a small set of squares in the top left hand corner of the board where the mouse and other devices plug in). There may be some small fan conenctors plugged in as well.
Be sure there are no cables or shrouds hanging anywhere near any fans (especially the cpu fan), and plug the power cord back in Also connect the keyboard and the monitor. Try to turn the PC on. If it boots up, it will get to a prompt asking you for a bootable disk. Just turn the PC back off and proceede with reasembly.
If nothing happens, try to unplug your memory sticks (one at a time if you have more then one). It is possible, depending on the age of your machine that you have to install the memory sequentially. In either case, you should get some beeps on restart if something is wrong. We will address that later if you get to that point.
If still nothing, try to remove all the memory sticks, and see if you get any beeps.
This is about where the step by step troubleshooting will have to stop. There are a few too many variables to cover removing a CPU without knowing more specifics about your system. Unless the CPU died, there is very little removing it will tell you. But the only way to really test it is with a similar system to see if the other system will post.
I don't know for certain if you will get a post code (beeps) without a CPU in place. This would only tell you for certain that the PSU (power supply) is "sorta" working. It may not be functioning properly enough to power up the board, fans, or components.
If you get to this point with still no beeps or no life, it is a pretty good chance that the PSU is dead, and I would hold off on worrying about the CPU. Chances are it is good. The options you have at this point would be to try another PSU, or try this one in a similar computer and see if you can power up. But, I am willing to bet you won't have a similar computer to test out.
Look at the PSU (big silverish box at the top of the case, where all the multi-colored cords are coming from), on the side facing out, there should be a sticker with some pertinent info, it should look similar to
this one There should be something to indicate the size (in Watts) of the PSU - in the picture above, it is a 430W PSU. This is most crittical. You will need another PSU of at least this size to replace your current one. In the link above, if you check some of the other pictures, you will see there is a long rectangular white plug, that has 20 connectors. It is possible to short one or two of these connectors together, and determine if the PSU will come on, and if it is working. Someone else will have to post specifics on that, and you will have to tell us first off if indeed you have an ATX type power supply (which is the kind with 20 pins) the other style (AT) will look similar to
this one.
If it turns out the PSU is dead, you have a few options. Depending on what you find out about your PSU (what type, what power, etc) it may be worthwhile to invest in a new one ($14 - $50 USD - before shipping). Some used electronics stores, or other types of PC repair places may have one localy for less. Depending on how old this really is, that may be a good alternative. A few phone calls will provide some pretty quick results.
The other choice is if the PC is too old to bother with, you can always salvage the data off your hard drive. I assume you have access to another computer, as you are posting on this forum. If this is not at home or a friends, you may not have a convenient way to salvage the data.
In either case, report back with your findings, and we will help you with the next step. Salvaging the data from the HDD is a pretty easy option, if you have another PC (or a working one) to plug it into.
If you get something working with the post beeps, and it turns out something was loose, reassembly is just the opposite of disassembly. The plugs from the drives must be aligned as stated above, and the cards must go back in their original slots. The side of the case will slide on from the back, or from being inserted into some holes before sliding forward. In either case, the final action is the side slides forward. Then the screws are reinstalled in the back, and all plugs hooked back up. Someone had posted a step by step link, that I believe had pictures, I will try to post it here for you to reference as well.
I hope this helps and doesn't confuse you. It really is a pretty asy procedure, and may sound more daunting then it really is. It is like anything, once you get into it, the steps make more sense when you see it all first hand,then they do when you read about it without ever having seen it.
If something is unclear or neds more explanation, let me know. Good thing you caught me on "wordy" day - lol...
Here is a picture for reference (although not very good)
