Lenovo 7749 Manuel D’Utilisation
Replacing
the
system
board
Attention
Do
not
open
your
computer
or
attempt
any
repair
before
reading
and
understanding
the
“Important
safety
information”
in
the
ThinkCentre
Safety
and
Warranty
Guide
that
came
with
your
computer.
To
obtain
a
copy
of
the
ThinkCentre
Safety
and
Warranty
Guide,
go
to:
http://www.lenovo.com/support
This
section
provides
instructions
on
how
to
replace
the
system
board.
CAUTION:
The
heat
sink
and
microprocessor
might
be
very
hot.
Turn
off
the
computer
and
wait
three
to
five
minutes
to
let
the
computer
cool
before
opening
the
computer
cover.
To
replace
the
system
board:
1.
Open
the
computer
cover.
See
2.
Pivot
the
drive
bay
assembly
upward
to
gain
access
to
the
system
board.
See
3.
Remove
the
hard
disk
drive.
See
4.
Remove
all
memory
modules
and
adapter
cards
that
are
currently
installed.
See
and
5.
Carefully
take
note
of
the
cable
routing
and
the
location
of
all
cable
connectors
on
the
system
board,
and
then
disconnect
all
the
cables.
See
6.
Remove
the
heat
sink
and
fan
assembly
from
the
failing
system
board.
See
7.
Remove
the
heat
sink
and
fan
assembly
retainer
by
releasing
the
four
screws
that
secure
the
retainer
on
the
system
board,
and
then
lifting
the
retainer
off
the
system
board.
8.
Carefully
slide
the
system
board
toward
the
front
of
the
chassis
so
that
it
can
be
released
from
the
four
mounting
studs
that
secure
the
system
board
in
place,
and
then
lift
the
system
board
out
of
the
chassis.
9.
Remove
the
microprocessor
socket
cover
from
the
new
system
board.
10.
Remove
the
microprocessor
from
the
failing
system
board
and
install
it
on
the
new
system
board.
See
11.
The
failing
system
board
must
be
returned
with
a
microprocessor
socket
cover
to
protect
the
pins
during
shipping
and
handling.
Install
the
microprocessor
socket
cover
removed
from
the
new
system
board
on
the
failing
system
board.
To
install
the
microprocessor
socket
cover:
a.
Make
sure
the
microprocessor
has
been
removed
from
the
microprocessor
socket,
and
then
close
the
microprocessor
retainer
and
lock
it
into
position
with
the
small
handle.
Chapter
9.
Replacing
FRUs
-
607
computers
147