Mechanical Requirements
16 LGA 771 Socket Mechanical Design Guide
Notes:
1. These specifications apply to uniform compressive loading in a direction perpendicular to the IHS top
surface.
2. This is the minimum and maximum static force that can be applied by the heatsink and retention solution
to maintain the heatsink and processor interface.
3. Loading limits are for the LGA771 socket.
4. Dynamic compressive load applies to all board thickness.
5. Dynamic loading is defined as an 11 ms duration average load superimposed on the static load
requirement.
6. Test condition used a heatsink mass of 1 lbm with 50g acceleration measured at heatsink mass. The
dynamic portion of this specification in the product application can have flexibility in specific values, but the
ultimate product of mass times acceleration should not exceed this dynamic load.
7. Transient bend is defined as the transient board deflection during manufacturing such as board assembly
and system integration. It is a relatively slow bending event compared to shock and vibration tests.
8. Refer to the processor Thermal Mechanical Design Guide for information on heatsink clip load metrology.
9. R is defined as the radial distance from the center of the LGA771 socket ball array to the center of the
heatsink load reaction point closest to the socket, as demonstrated in Figure3-2.
10. Applies to populated sockets in fully populated and partially populated socket configurations.
11. Through life or product. Condition must be satisfied at the beginning of life and at the end of life.
12. Rigid backing is not allowed. The board should flex in the enabled configuration.
Table 3-2. Socket Loading Specifications
Parameter Board
Thickness R10 Min Max Unit Notes
Static
Compressive Load
Apply for all
board
thickness
from
1.57mm
( 0.062” )
to 2.54mm
( 0.100” )
25mm
< R <
45mm
80
18
133
30
N
lbf
1,2,3,8,
9,10,
11,12
R >45m m 80
18
311
70
N
lbf
Dynamic
Compressive Load
NA NA NA 311 N (max static compressive
load) + 222 N dynamic loading
70 lbf (max static compressive
load) + 50 lbf dynamic loading
N
lbf
1,3,4,
5,6
Trans ient Ben d
Limits
1.57mm
0.062”
NA NA 750 με 1,3,7
2.16mm
0.085”
700
2.54mm
0.100”
650