CN110708932B - Radiator and PCB heat dissipation component and server having the same - Google Patents

Abstract

The present invention discloses a heat sink and a PCB heat sink assembly and a server having the same. The heat sink is suitable for being arranged at a position upstream of a heat sink airflow adjacent to a device to be cooled. The heat sink comprises: an upstream heat sink and a support. The support is connected to one end of the upstream heat sink facing the device to be cooled, and one end of the support facing away from the upstream heat sink is suitable for being connected to the device to be cooled, wherein the resistance of the support to the heat sink airflow is less than the resistance of the upstream heat sink to the heat sink airflow. By arranging the support between the upstream heat sink and the device to be cooled, the heat sink airflow is promoted to flow from the vicinity of the support to the downstream, thereby reducing the temperature of the downstream heat sink airflow, thereby reducing the temperature of the downstream device to be cooled, and preventing the PCB heat sink assembly from being damaged due to excessive temperature.

Description

Radiator and PCB heat dissipation component and server having the same

Technical Field

The present invention belongs to the technical field of PCB heat dissipation, and in particular, relates to a radiator and a PCB heat dissipation component and a server having the radiator.

Background Art

In the field of PCB heat dissipation, there is a common problem with the layout of multiple rows of chips distributed in series along the air duct. The heat sink of the upstream chip in the air duct dissipates heat first, and the hot air after dissipation is blown to the heat sink of the downstream chip, and the heat sink of the downstream chip is exposed to a higher temperature. In order to improve the heat dissipation efficiency of the chassis and control the temperature of the downstream chip below the expected value, the commonly used method in the heat dissipation solution is to increase the heat dissipation area of the downstream heat sink or enhance the convection heat transfer capacity of the air. Its essence is to reduce the thermal resistance in the heat dissipation path between the air and the chip. However, when the thermal resistance is very small, the cost-benefit ratio of this heat dissipation solution will gradually increase.

Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a radiator, which can change the temperature distribution of air flowing through a downstream radiator, reduce the temperature of the downstream radiator, and thus improve the heat dissipation efficiency.

The invention also provides a PCB heat dissipation component having the heat sink.

The present invention also provides a server having the PCB heat dissipation component.

According to the radiator of the first aspect of the present invention, the radiator is suitable for being arranged at a position upstream of a heat dissipation airflow adjacent to a device to be cooled, the radiator comprises: an upstream heat dissipation portion and a support, the upstream heat dissipation portion is provided with a plurality of upstream heat dissipation fins, an upstream heat dissipation flow channel is defined between adjacent upstream heat dissipation fins, the support is connected to one end of the upstream heat dissipation portion facing the device to be cooled, and the end of the support facing away from the upstream heat dissipation portion is suitable for being connected to the device to be cooled, wherein the resistance of the support to the heat dissipation airflow is less than the resistance of the upstream heat dissipation portion to the heat dissipation airflow.

According to the heat sink of the embodiment of the present invention, a support is set between the upstream heat dissipation part and the device to be cooled, so as to promote the heat dissipation airflow to flow from the vicinity of the support to the downstream, thereby reducing the temperature of the downstream heat dissipation airflow, and then reducing the temperature of the downstream device to be cooled, thereby preventing the PCB heat dissipation component from being damaged due to excessive temperature.

In addition, the radiator according to the embodiment of the present invention may also have the following additional technical features:

According to some embodiments of the present invention, the upstream heat dissipation part further includes: a tooth base plate, the tooth base plate is connected to the support platform, and the plurality of upstream heat dissipation fins are all connected to the tooth base plate.

According to some embodiments of the present invention, a diffusion rib is provided on the upstream heat dissipation fin located in the middle of the width direction of the gear base plate, and the diffusion rib is provided at an end of the upstream heat dissipation fin away from the support platform.

According to some embodiments of the present invention, the support platform includes: supporting ribs and conductive ribs, the supporting ribs are connected to the upstream heat dissipation part, the conductive ribs are connected to the side of the supporting ribs facing away from the upstream heat dissipation part and are arranged perpendicular to the supporting ribs, and the surface of the conductive ribs facing away from the supporting ribs is suitable for fitting and connecting to the device to be cooled.

According to some embodiments of the present invention, a projection pattern of the conductive rib on a surface of the device to be cooled that faces the heat sink covers a projection pattern of the supporting rib on a surface of the device to be cooled that faces the heat sink.

According to some embodiments of the present invention, there are two support ribs, the conductive rib is disposed between the two support ribs, and the two support ribs, the conductive rib and the tooth base plate cooperate to define a sweeping flow channel.

According to some embodiments of the present invention, the total thickness of the supporting ribs is smaller than the total thickness of the upstream heat dissipation fins.

According to the second aspect of the present invention, the PCB heat dissipation assembly comprises: a PCB circuit board, a heat sink according to the above-mentioned embodiment and a downstream heat dissipation part, the PCB circuit board has a plurality of chips, the end of the support platform facing away from the upstream heat dissipation part is connected to a chip located upstream of the heat dissipation airflow among the plurality of chips, the downstream heat dissipation part is provided with a plurality of downstream heat dissipation fins, a downstream heat dissipation channel is defined between adjacent downstream heat dissipation fins, and the downstream heat dissipation part is connected to a chip located downstream of the heat dissipation airflow among the plurality of chips.

According to some embodiments of the present invention, the upstream heat dissipation fins are arranged in parallel with the downstream heat dissipation fins, and in a direction perpendicular to the upstream heat dissipation fins and the downstream heat dissipation fins, the upstream heat dissipation fins are arranged spaced apart from the downstream heat dissipation fins.

A server according to an embodiment of the third aspect of the present invention comprises a PCB heat dissipation assembly and a fan according to the above embodiment, wherein the heat sink is arranged opposite to a hub of the fan.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

FIG1 is a schematic structural diagram of a heat sink according to an embodiment of the present invention;

FIG2 is a schematic structural diagram of a heat sink according to another embodiment of the present invention;

FIG3 is a schematic diagram of a partial structure of a PCB heat dissipation assembly according to an embodiment of the present invention;

FIG4 is a schematic diagram of a partial structure of a PCB heat dissipation assembly according to another embodiment of the present invention;

FIG5 is a schematic diagram of the cooperation between a fan and a PCB heat dissipation assembly in a server according to an embodiment of the present invention (the direction of the arrow in the figure refers to the direction of the heat dissipation airflow);

FIG6 is a schematic diagram of the cooperation between a fan and a PCB heat dissipation assembly in a server according to another embodiment of the present invention (the direction of the arrow in the figure refers to the direction of the heat dissipation airflow).

Reference numerals:

100: PCB heat dissipation component;

10: radiator; 11: upstream heat dissipation unit; 12: upstream heat dissipation fins; 13: support platform;

14: tooth base plate; 15: diffusion ribs; 16: support ribs; 17: conduction ribs;

20: PCB circuit board; 21: chip; 30: downstream heat dissipation unit;

40: fan; 41: hub; 42: blades.

DETAILED DESCRIPTION

Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

The following describes a heat sink 10 and a PCB heat dissipation assembly 100 and a server having the same according to an embodiment of the present invention with reference to FIGS. 1 to 6 .

According to the heat sink 10 of the embodiment of the present invention, the heat sink 10 is suitable for being arranged at a position adjacent to the upstream of the heat dissipation airflow of the device to be cooled. A fan 40 is arranged in the server. The fan 40 blows air toward the PCB heat dissipation assembly 100 to dissipate heat for the PCB heat dissipation assembly 100. The airflow generated by the fan 40 forms a heat dissipation airflow on the PCB heat dissipation assembly 100. The heat dissipation airflow blows from the fan 40 to the heat dissipation assembly 100. In the direction from the fan 40 to the PCB heat dissipation assembly 100, the position adjacent to the fan 40 is formed as the upstream position of the heat dissipation airflow relative to the position away from the fan 40. That is, the fan 40 is arranged on one side of the PCB heat dissipation assembly 100, the position of the PCB heat dissipation assembly 100 adjacent to the fan 40 is formed as the upstream position of the heat dissipation airflow, and the position of the PCB heat dissipation assembly 100 away from the fan 40 is formed as the downstream position of the heat dissipation airflow.

In this embodiment, the devices to be cooled refer to a plurality of chips 21 arranged on a PCB cooling assembly 100 , and the heat sink 10 is arranged at an upstream position, which means that the heat sink 10 is arranged on a portion of the plurality of chips 21 adjacent to the fan 40 .

The heat sink device in this embodiment refers to computing chips arranged in multiple columns or rows in a regular pattern, and can also be other heat generating bodies arranged in a similar regular pattern. The heat sink 10 includes an upstream heat sink 11 and a support 13 .

Among them, a plurality of upstream heat dissipation fins 12 are provided on the upstream heat dissipation part 11, and the heat dissipation fins achieve the purpose of heat dissipation through thermal convection of air. An upstream heat dissipation channel is defined between adjacent upstream heat dissipation fins 12. The airflow takes away the heat of the upstream radiator 10 by thermal convection through the upstream heat dissipation channel. There are a plurality of upstream heat dissipation fins 12 on an upstream heat dissipation part 11.

The support 13 is connected to one end of the upstream heat dissipation part 11 facing the device to be cooled (the chip 21 as shown in FIG3 ), and the end of the support 13 facing away from the upstream heat dissipation part 11 is suitable for being connected to the device to be cooled, and the heat dissipation fins are connected to the components to be cooled through the support 13, wherein the resistance of the support 13 to the cooling airflow is less than the resistance of the upstream heat dissipation part 11 to the cooling airflow.

As shown in FIGS. 1 and 2 , in this embodiment, the support 13 is in direct contact with the surface of the device to be cooled. The heat on the surface of the device to be cooled is first transferred to the support 13 by heat conduction. The cooling airflow generated by the cooling fan is divided into two parts. One part of the airflow passes through the upstream cooling channel and takes away the heat of the upstream cooling fins 12 by thermal convection. Another part of the airflow blows from the support 13 of the radiator 10 to the downstream cooling structure, and then takes away the heat of the downstream cooling structure by thermal convection. Finally, the air flow in the chassis takes the heat of the air around the upstream cooling fins 12 and the downstream cooling structure to the outside of the chassis by thermal convection. Since the support 13 has a small resistance to the airflow, a large part of the airflow flows downstream through the vicinity of the support 13. The airflow flowing through the support 13 only exchanges heat with the support 13. Compared with the upstream cooling part 11, the heat exchange efficiency between the support 13 and the airflow is low. When the cooling airflow flows from the vicinity of the support 13 to the downstream, the temperature is low, which can enhance the cooling effect on the cooling structure at the downstream position of the cooling airflow.

In the prior art, the heat of the upstream heat dissipation structure of the heat sink 10 is carried to the downstream heat dissipation structure by the airflow, resulting in a higher overall wind temperature of the heat dissipation structure of the downstream chip 21 of the air duct, and poor heat dissipation efficiency of the downstream chip 21, resulting in poor overall temperature uniformity of the chip on the PCB board. In order to control the temperature of the downstream chip 21 below the expected value, the commonly used method in the heat dissipation solution is to increase the heat dissipation area of the downstream heat dissipation structure, enhance the convective heat transfer capacity of the air, or improve the thermal conductivity of the heat dissipation structure material. Its essence is to reduce the thermal resistance in the heat dissipation path between the air and the chip 21. Although it will increase the heat dissipation efficiency of the heat dissipation structure, when the thermal resistance is very small, the cost-benefit ratio of this heat dissipation solution will gradually increase.

Therefore, according to the heat sink 10 of the embodiment of the present invention, by setting a support platform 13 between the upstream heat dissipation part 11 and the device to be cooled, the heat dissipation airflow is promoted to flow from the vicinity of the support platform 13 to the downstream, thereby reducing the temperature of the downstream heat dissipation airflow, thereby improving the heat exchange efficiency between the downstream heat dissipation airflow and the downstream heat dissipation structure, thereby preventing the device to be cooled from accumulating heat at the downstream position of the heat dissipation airflow, improving the heat dissipation capacity of the chip at the downstream position, and providing better temperature uniformity for the chips on the entire PCB board.

According to the heat sink 10 of the embodiment of the present invention, the upstream heat sink 11 further includes: a tooth base plate 14, the tooth base plate 14 is connected to the support 13, and multiple upstream heat sink fins 12 are all connected to the tooth base plate 14. Through the tooth base plate 14, multiple heat sinks can be connected to the support 13, reducing the area of the support 13 of a single heat sink 10, that is, reducing the resistance of the support 13 to the hot air flow and increasing the air flow rate. In addition, the number of upstream heat sink fins 12 in the upstream heat sink 11 can be increased, thereby improving the heat dissipation efficiency of the upstream heat sink 11.

According to the radiator 10 of the embodiment of the present invention, a diffusion rib 15 is provided on the upstream heat dissipation fin 12 located in the middle of the width direction of the tooth base plate 14, and the diffusion rib 15 is located at the end of the upstream heat dissipation fin 12 away from the support 13. By providing the diffusion rib 15, the airflow in the upstream heat dissipation channel can exchange heat with the diffusion rib 15 when flowing out of the upstream heat dissipation channel from the side away from the tooth base plate 14, thereby increasing the heat dissipation area of the upstream radiator 10 and increasing the heat dissipation efficiency of the upstream heat dissipation part 11. Providing the diffusion rib 15 in the middle of the width direction of the tooth base plate 14 can also increase the structural stability of the radiator 10.

According to the heat sink 10 of the embodiment of the present invention, the support platform 13 includes: support ribs 16 and conductive ribs 17, the support ribs 16 are connected to the upstream heat dissipation part 11, the conductive ribs 17 are connected to the side of the support ribs 16 facing away from the upstream heat dissipation part 11 and are arranged perpendicular to the support ribs 16, and the surface of the conductive ribs 17 facing away from the support ribs 16 is suitable for fitting and connecting to the device to be cooled, that is, the conductive ribs 17 are located between the support ribs 16 and the device to be cooled, and the function of the conductive ribs 17 is to transfer the heat of the device to be cooled to a plurality of heat dissipation fins through heat conduction, and the heat on the heat dissipation fins is then transferred to the outside of the chassis through thermal convection of the airflow.

The support platform 13 is formed by the cooperation of the support ribs 16 and the conductive ribs 17 . Not only can the support ribs 16 be used to support the upstream heat dissipation part 11 , but the conductive ribs 17 can also be used to diffuse the heat from the device to be dissipated, which is beneficial to further improve the heat dissipation efficiency of the radiator 10 .

According to the heat sink 10 of the embodiment of the present invention, the projection pattern of the conductive ribs 17 on the surface of the device to be cooled facing the heat sink 10 covers the projection pattern of the support ribs 16 on the surface of the device to be cooled facing the heat sink 10, that is, the contact area between the conductive ribs 17 and the device to be cooled is larger than the contact area between the support ribs 16 and the conductive ribs 17. By increasing the area of the conductive ribs 17, the conduction efficiency can be increased, thereby increasing the heat dissipation efficiency of the heat sink 10.

As shown in FIG. 2 , according to some specific embodiments of the present invention, there are two support ribs 16, and the conductive rib 17 is arranged between the two support ribs 16. The two support ribs 16, the conductive rib 17 and the tooth base plate 14 cooperate to define a swept flow channel. By setting two support ribs 16, the total area of the support ribs 16 can be increased, which can not only increase the structural stability of the heat sink 10, but also improve a certain heat dissipation capacity and reduce the working pressure of the upstream heat dissipation part. Moreover, the swept flow channel defined between the two support ribs 16 can transfer heat with the two support ribs when the heat dissipation airflow passes through the swept flow channel, which can improve the heat dissipation efficiency of the heat sink 10 to a certain extent, and can adjust the heat dissipation balance of the PCB heat dissipation assembly 100 with the downstream heat dissipation part 30. For example, for a PCB heat dissipation assembly 100 with a smaller downstream heat dissipation pressure, two support ribs 16 can be set in the upstream heat sink 10, and for a PCB heat dissipation assembly 100 with a larger downstream heat dissipation pressure, a single support rib 16 can be set in the upstream heat sink 10.

According to the radiator 10 of the embodiment of the present invention, the wind cross-section of the support rib 16 is smaller than the wind cross-section of the upstream heat dissipation fins 12, because the airflow is divided into two parts when passing through the upstream heat dissipation fins 12, one part takes away the heat of the upstream heat dissipation fins 12 by thermal convection, and the other part of the airflow is blown from the support platform 13 of the radiator 10 to the downstream radiator 10. By reducing the wind cross-section of the support rib 16, the obstruction of the support rib 16 to the heat dissipation airflow can be reduced, and the airflow is promoted to pass through the lower layer of the upstream radiator 10, thereby increasing the airflow passing through the downstream radiator 10, and thus the heat dissipation efficiency of the downstream heat dissipation structure can be improved.

The PCB heat dissipation assembly 100 according to the second embodiment of the present invention further includes: a PCB circuit board 20, a downstream heat dissipation portion 30 and the heat sink 10 described in the above embodiment.

As shown in Figures 3 and 4, there are multiple chips 21 on the PCB circuit board 20, and the multiple chips 21 can be distributed in multiple rows and columns. There is a heat dissipation airflow on the PCB circuit board 20 that flows along the arrangement direction of the chips 21 (the direction shown by the arrows in Figures 5 and 6), and the end of the support 13 facing away from the upstream heat dissipation part 11 is connected to the chip 21 located upstream of the heat dissipation airflow among the multiple chips 21, that is, the conductive rib 17 on the support 13 is connected to the chip 21 upstream of the heat dissipation airflow, and the conductive rib 17 can transfer the heat generated by the chip 21 to the upstream heat dissipation fins 12, and then take away the heat in the upstream heat dissipation fins 12 through the airflow.

The downstream heat dissipation part 30 is connected to the chip 21 located downstream of the heat dissipation airflow among the multiple chips 21, which means that the heat sink 10 is arranged on the part of the multiple chips 21 far away from the fan 40, wherein the downstream heat dissipation part 30 is provided with multiple downstream heat dissipation fins, and a downstream heat dissipation channel is defined between adjacent downstream heat dissipation fins, and the downstream heat dissipation fins achieve the purpose of heat dissipation through heat convection of air. The airflow takes away the heat of the downstream heat sink 10 by heat convection through the downstream heat dissipation channel.

When the heat dissipation airflow passes through the radiator 10 located upstream, part of the airflow passes through the upstream heat dissipation part 11, and part of the airflow passes through the support 13. The two parts of the airflow converge at the downstream heat dissipation part 30 and cooperate with the downstream heat dissipation part 30 to dissipate heat. Since the temperature of the airflow passing through the support 13 is relatively low, the temperature of the airflow passing through the downstream heat dissipation part 30 can be reduced, thereby improving the heat dissipation efficiency of the downstream heat dissipation part 30.

According to the PCB heat dissipation assembly 100 of the embodiment of the present invention, by adopting the heat sink 10 with the above structure, the temperature of the downstream heat dissipation airflow can be reduced, thereby improving the heat exchange efficiency between the downstream heat dissipation airflow and the downstream heat dissipation part 30, improving the temperature uniformity of the chip at different positions of the PCB circuit board 20, and improving the overall computing power of the chip on the entire PCB board.

According to the radiator 10 of the embodiment of the present invention, the upstream heat dissipation fins 12 are arranged in parallel with the downstream heat dissipation fins, and in the direction perpendicular to the upstream heat dissipation fins 12 and the downstream heat dissipation fins, the upstream heat dissipation fins 12 and the downstream heat dissipation fins are spaced apart from each other. By arranging the upstream heat dissipation fins 12 in parallel with the downstream heat dissipation fins, the number of heat dissipation fins can be increased to the greatest extent, and the resistance of the upstream heat dissipation fins 12 and the downstream heat dissipation fins to the heat dissipation airflow can be reduced.

The upstream heat dissipation fins 12 are spaced apart from the downstream heat dissipation fins, so that the heat dissipation airflow flowing out of the upstream heat dissipation channel can fully contact the downstream heat dissipation fins, thereby improving the heat dissipation efficiency of the downstream heat dissipation part 30 and preventing heat accumulation in the chip 21 downstream of the heat dissipation airflow.

The server according to the third aspect of the present invention comprises the PCB heat dissipation assembly 100 and the fan 40 described in the above embodiment, the fan blades of the fan 40 comprise a hub 41 and blades 42 connected to the hub 41, the heat sink 10 is arranged opposite to the hub 41 of the fan 40, and the downstream heat dissipation portion 30 is arranged opposite to the blades 42 of the fan 40. Since the wind flow velocity of the fan 40 near the hub 41 is relatively low, and the wind flow near the blade 42 is relatively high, the server with the above structure can ensure that the PCB heat dissipation assembly 100 is located at the downstream chip with better heat dissipation effect, thereby ensuring that the PCB heat dissipation assembly 100 dissipates heat evenly and prevents local heat accumulation.

Other structures and operations of the server according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

In the description of the present invention, "first feature" or "second feature" may include one or more of the features.

In the description of the present invention, "plurality" means two or more.

In the description of the present invention, a first feature being “on” or “under” a second feature may include that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact with each other but are in contact with each other via another feature therebetween.

In the description of the present invention, “on”, “over” and “above” a first feature from a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims (7)

1. A PCB heat sink assembly, comprising:

The PCB is provided with a plurality of chips which are arranged in series;

A heat sink adapted to be disposed at a location of a device to be heat-dissipated adjacent upstream of a heat dissipating airflow, the heat sink comprising:

An upstream heat dissipation part, wherein a plurality of upstream heat dissipation tooth sheets are arranged on the upstream heat dissipation part, and an upstream heat dissipation flow channel is defined between adjacent upstream heat dissipation tooth sheets;

The support platform is connected to one end of the upstream heat dissipation part, facing the device to be heat-dissipated, and one end of the support platform, facing away from the upstream heat dissipation part, is suitable for being connected to the device to be heat-dissipated;

Wherein the resistance of the platform to the heat dissipation air flow is smaller than the resistance of the upstream heat dissipation part to the heat dissipation air flow;

the pallet includes:

the support ribs are connected with the upstream radiating part;

The conduction muscle, the conduction muscle is connected the back of the supporting rib one side of upstream radiating portion and with the supporting rib sets up perpendicularly, the conduction muscle is back of the supporting rib one side surface is suitable for the laminating to be connected wait to dispel the heat on the device, the supporting rib is two, the conduction muscle is established two between the supporting rib, upstream radiating portion still includes: the tooth base plate, two supporting ribs, the conducting ribs and the tooth base plate are matched to define a flow sweeping channel, and one end of the supporting table, which is opposite to the upstream radiating part, is connected to a chip, which is located upstream of the radiating airflow, of the chips

The downstream heat dissipation part is provided with a plurality of downstream heat dissipation tooth sheets, a downstream heat dissipation flow channel is limited between the adjacent downstream heat dissipation tooth sheets, the downstream heat dissipation part is connected to a plurality of chips positioned at the downstream of the heat dissipation airflow, the heat dissipater is arranged opposite to the hub of the fan, and the downstream heat dissipation part is arranged opposite to the blades of the fan.

2. The PCB heat sink assembly of claim 1, wherein the tine base plate is connected to the tray table and a plurality of the upstream heat dissipating tines are each connected to the tine base plate.

3. The PCB heat sink assembly of claim 1, wherein the upstream heat sink fins located at the middle of the width direction of the tine substrate are provided with diffusion ribs, the diffusion ribs being provided at one end of the upstream heat sink fins away from the pallet.

4. The PCB heat sink assembly of claim 1, wherein the projected pattern of the conductive ribs on the surface of the device to be heat dissipated facing the heat sink covers the projected pattern of the support ribs on the surface of the device to be heat dissipated facing the heat sink.

5. The PCB heat sink assembly of claim 1, wherein the total thickness of the support ribs is less than the total thickness of the upstream heat dissipating fins.

6. The PCB heat sink assembly of claim 1, wherein the upstream heat sink tine is disposed in parallel with the downstream heat sink tine and the upstream heat sink tine is disposed in spaced relation to the downstream heat sink tine in a direction perpendicular to the upstream heat sink tine and the downstream heat sink tine.

7. A server for a server, which comprises a server and a server, characterized by comprising the following steps:

the PCB heat sink assembly of any one of claims 1-6.