i think u will be able to understand

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How to Assemble and Build A PC


Installing the
motherboard:

Make sure you have all the
components in place and a nice,
clean and big enough place to work
with.
Put your antic-static wrist strap on to
prevent your components from
getting affected. Make sure your
hands are clean before starting. First
we will be installing the motherboard
which is a piece of cake to install.
· Open the side doors of the cabinet
· Lay the cabinet on its side
· Put the motherboard in place
· Drive in all the required screws
Tip: Most motherboards come with an antistatic bag. It is advisable to put the
motherboard on it for some time and then remove it from the antistatic bag before placing
it in the cabinet.