What are the steps in the assembly of a desktop pc?

Make sure you get the manuals to the motherboard which is very essential for the connections.

For rest have a look on these pages:

http://www.mysuperpc.com/pc_assembly/computer_parts_list.shtml


http://www.regstevens.co.uk/assy.htm

http://www.buildeasypc.com/hw/howto/assemblepc.htm

1) I would pick out a case you like first. make sure it has what you want like a window on the side, USB connectors in the front, etc... room for your drives.
2) Pick out a good quality power supply... something with Active PFC.  Antec neopower 480W for example.. Or Zalman PSU. (quiet)
3) Order the parts you want... and... if at all possible... pick the color of your drives to match your case... like black or beige if you can.
4) Open the case and get the goodies out... nuts screws standoffs or whatever.
5) Put the standoffs in the case.
6) Break out the motherboard and mount your chip and RAM.  CPU will ONLY go in 1 way.  The ZIF socket lever will be in an up position before you drop the chip in to place.  Then... lower the lever... and put the Heatsink and Fan on top.  The RAM will plunk in too.
7) Put the I/O plate in the case
8) Put the motherboard with CPU and RAM in to the case on to the standoffs and screw it in.
9) Put in the drives
10) Put your video card in if this applies
11) Hook up the I/O connectors from front of PC.
12) Hook up the power supply
13) Test run the puppy.

Jeff
at yourtechonline.com

Stuff that you'll be needing to buy before assembling:

1. Case
2. Power supply (if you don't want the one that's built into your case)
3. Processor (Pentium 4, in your case)
4. Motherboard (Socket 478, in your case; make sure you get the manual)
5. RAM (depending on the type of the board)
6. Video card (avoid buying a motherboard that's got graphics built-in)
7. Hard drive(s)
8. CD/CD-RW/DVD drive (for optical media)
9. Sound card (built-in sound in a motherboard is also good)
10. Modem (for Internet connectivity)
11. LAN card (for networking)
12. Keyboard and mouse
13. Diskette drive (in case you need one)
14. Speakers
15. AVR/UPS

Before you start, (and while i agree with what others here have said) you need to ask yourself how much money are you going to spend.

How much money are you going to spend?

If you're unsure of what brands of components to select, I'd highly recommend the Ars System Guide from arstechnica.com.  I've relied on it many times to select components.  They have a highly knowledgeable staff and are right up there with tomshardware.com as being an authority on computer hardware and other geekery.

April 2005 Edition of the Ars System Guide
http://arstechnica.com/guides/buyer/system-guide-200504.ars

1) Purchase an ATX case. The case may or may not come with a power supply. It is ok if it does or not.
2.)Purchase a brand-name power-supply, ie. Antec, PC & Power Cooling, etc. The bare-minumum should be at least 400watts.
3)Purchase memory, i would recommend at least 512mb. Make sure its brand-name ie. Kingston, Corsair, etc.
4)Begin by installing the power supply. Next, look onto the motherboard for where the CPU is going to go. There should be a lever on one of the sides of the socket. Lift the lever. Now, on one of the sides of the CPU, the tip of the side will be missing. Alike on the socket. Align the misssing peices together.****NO FORCE IS NEEDED***** the cpu will fall in automatically. You do not need to push it in!! Next, get some thermal grease and place a small dab of it in the center of the cpu. **YOU DO NOT NEED ANY MORE THAN THAT**. The purpose of the thermal grease is to improve the contact between the Heatsink and CPU. Now look at the cpu. There will be a bevel, which has to be alined where the CPU socket is slightly raised. Alight the Heatsink correctly and attatch one of the clips of the heatsink. Now get a flat-head screw-driver and gently put pressure on the other side of the clip and push inward until it falls into place. Make sure the heatsink is secured. Now take your RAM and make sure it is alined to the RAM socket, (One side of the RAM is longer than the other, the same with the socket). Once you have alined them open the tabs on the sides of the RAM socket, and gently press the RAM down until the clips come up and secure the ram. Now, using your motherboard Spacers (They come with your motherboard), secure them to the case where you will screw the motherboard to them. ***DO NOT PUT MORE THAN YOU NEED, THEY WILL SHORT THE MOTHERBOARD**. Once you have installed the spacers, install the I/O backplate if it came with your motherboard, and then secure the motherboard to the case. Configure the jumpers on the back of the drives, the fastest drive should be master and the other slave. Put the harddrive on a seprate cable then the cd-rom drives becasue it is faster.  Take all your drives align them with the front of your case, and screw them down. Now, take the IDE cables (Usually white ribbon cables) and attatch one side to the motherboard and the other to the drive. Push gently on these cables, if they do not fit turn them around. Now you have wires which came with your case for the buttons and the LEDS. There destination should be silk-screened on the motherboard or look up thier location in the motherboard manual. Hook these up. If they do not work when you boot up your system, just flip them around. Now install fans onto the back of the case and front. Remember the label is the side which blows the air out. Now hook up all the prehiperals with the power cables.
5)Organize everything in your case with zip-ties and make sure there is adequate air-flow.
6)Upon powering up your system, check to make sure the CPU fan turns on. If not, immediately power down the computer, and fix the problem.
-Good Luck! Hope this helped!
-techsupport_[101]

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