These instructions will teach you how to build a desktop computer. Here are some steps you should take. When you finish assembling all the components, you will have a computer for you and you can design a system that is more in line with your use.
Steps

Step 1. Prepare the motherboard which in this case is an NVIDIA model
If you want a good computer, use an Intel G31, GMA3100, or AMD 780 motherboard.

Step 2. Mount the CPU in the motherboard slot
You must choose the correct CPU for your motherboard, and install it according to the instructions. Be careful not to install the CPU incorrectly. Not only will your computer not work, it could create a short circuit and damage your motherboard.

Step 3. Connect the CPU cooler to the motherboard

Step 4. Attach the RAM modules into the corresponding slots
The motherboard should have 2 rows of slots that have 2 or 3 sections of different lengths. Make sure the pins on the RAM line up with the pins on the motherboard connector. Don't confuse the RAM slots with the PCI slot. PCI slots are usually wider.

Step 5. Open the cabinet and mount the power supply, which in this case is an M-ATX type
Make sure to connect all connections to the drives and to the motherboard.

Step 6. Attach the motherboard to the back plate of the enclosure and check the mounting positions of the motherboard
The instructions on the card should tell you the position of the card.

Step 7. Properly place the motherboard in the enclosure

Step 8. Mount the hard drive and connect it to the motherboard as well as to the power source
There should be separate connections for the power supply and the motherboard. In case you have a SATA hard drive, you should remove the jumper.

Step 9. Connect the SATA connectors to the drives, the USB connectors and the enclosure switches to the motherboard
Your enclosure and motherboard instructions should tell you where to connect the cables.

Step 10. Connect the ATX 20 or 40-pin connector and the 4-pin power connector to the motherboard

Step 11. Mount the DVD-ROM drive
After connecting the ATA cables to the device, connect it to the power source.

Step 12. Finally, select a compatible operating system and follow the instructions to install it
Advice
- Read the instructions on the computer.
- Keep all instruction manuals.
Warnings
- Don't push too hard to install.
- Do not turn on the computer until it is fully connected.