JP6159370B2 - Server board water cooling structure - Google Patents

Description

  The present invention relates to a water-cooling structure for water-cooling a server board on which arithmetic elements (CPU) and storage elements (memory) such as ROM and RAM are mounted with high density.

  Patent Document 1 describes a structure for water-cooling an electronic component mounted on a board. In the structure described in Patent Document 1, a heat transfer block that sandwiches both ends of the board on which the electronic component is mounted is provided, and the surface of the board opposite to the surface on which the electronic component is mounted is provided. The end portion of the heat pipe provided along the side extends to the heat transfer block. The heat transfer block is attached to a water cooling rail through which cooling water is circulated. In the structure described in Patent Document 1, the heat generated in the electronic component is conveyed to the heat transfer block by the heat pipe, and the heat transfer block is cooled by the cooling water. Indirectly cooled by.

  Since the cooling water which is a cooling medium described in Patent Document 1 has a large specific heat, a large amount of heat can be carried by a small amount of cooling water. In addition, since heat is transferred from the electronic component to the cooling water by the heat pipe, the interval between the electronic components can be narrowed compared to the case where so-called air cooling is performed. Therefore, in the configuration described in Patent Document 1, even when the mounting density of electronic components is high, the electronic components can be sufficiently cooled, and the overall structure of the electronic device such as a server can be reduced. Can be achieved.

JP2013-69087A

  Recently, it has been demanded to further increase the information processing speed by electronic devices such as servers. For this reason, not only the memory packaging density is increased, but the memory and CPU (computing element) are combined. It has been started to be mounted on the board. For this reason, the amount of heat generated by this type of board (server board) is increasing, and it is conceivable to adopt a water cooling structure for cooling. As described above, the amount of water required for cooling can be reduced due to the large specific heat of the cooling water. On the other hand, since the specific gravity of the cooling water is large, if water cooling pipes are connected to both the memory and the CPU, the amount of cooling water increases and the weight of the entire electronic device such as a server increases. There is an inconvenience. Further, since the memory piping and the CPU piping coexist, the space for attaching and detaching the memory board is restricted, and the replacement operability may be impaired. Further, as piping becomes complicated, the number of places to be sealed increases, which may cause an increase in cost.

  The present invention has been made paying attention to the above technical problem, and an object thereof is to provide a water-cooling structure for a server board that can be simplified or reduced in weight without impairing the cooling performance. It is.

  In order to achieve the above object, the present invention provides a water cooling structure for a server board in which a server board on which an arithmetic element and a plurality of memory boards to which a storage element is mounted is mounted is cooled with cooling water. A plurality of heat receiving plates disposed between and receiving heat from the memory board; a heat pipe connected to the heat receiving plate; and the arithmetic element being brought into contact with the heat transferable and through the heat pipe It is characterized by comprising a cold plate to which heat is transmitted from the heat receiving plate, and a flow passage formed inside the cold plate and through which cooling water flows.

  In the present invention, the heat pipe includes a first heat pipe connected to the heat receiving plate, and a second heat pipe having one end connected to the cold plate so that heat can be transferred, A heat transfer block in which at least one end of one heat pipe and the other end of the second heat pipe are connected may be further provided.

  In the present invention, the first heat pipe has a thin plate-like flat portion, and the flat portion is embedded in the heat receiving plate so as not to protrude from the surface of the heat receiving plate so that heat can be transferred to the heat receiving plate. It may be connected.

  In the present invention, the at least one end of the first heat pipe connected to the heat transfer block, and the other end of the second heat pipe connected to the heat transfer block, One end of the heat transfer block is inserted into the heat transfer block, and the other end connected to the heat transfer block is formed into a thin flat plate portion and the heat transfer block. It may be stuck to the outer surface of the.

  In the present invention, the one end of the second heat pipe is formed in a flat shape, and the one end of the flat second heat pipe is formed on an outer surface of the cold plate. It may be fitted in the groove and connected to the cold plate so as to be able to transfer heat.

  In the present invention, the heat receiving plate is disposed on both sides of the memory board with a predetermined one memory board interposed therebetween, and the heat receiving plates for connecting the heat receiving plates on both sides with the one memory board interposed therebetween are capable of transferring heat. A heat pipe may be further provided.

  The present invention may further include a heat transfer panel that is inserted between the heat receiving plate and the memory board and is brought into close contact with the memory board.

  The present invention may further include an elastic panel that is inserted between the heat transfer panel and the heat receiving plate to make the heat transfer panel approach the memory board.

  According to the present invention, since the cooling water takes heat from the cold plate by flowing the cooling water through the flow path inside the cold plate, the arithmetic element in contact with the cold plate is cooled by the cooling water via the cold plate. To be cooled. On the other hand, since the heat receiving plate is in contact with the memory board, the heat generated in the memory element, that is, the heat of the memory board is transmitted to the heat receiving plate, and is transmitted from the heat receiving plate to the cold plate by the heat pipe. Since cooling water flows through the flow path inside the cold plate, the heat transferred from the heat receiving plate to the cold plate via the heat pipe is taken away by the cooling water. Eventually, the memory board is indirectly cooled by the cooling water. Therefore, in the present invention, if the cooling water is circulated inside the cold plate, the arithmetic element and the storage element, that is, the memory board can be simultaneously cooled with water, and the piping for supplying and discharging the cooling water is simplified. As a result, a space required for replacing the memory board can be secured, and the replacement of the memory board becomes easy. Further, since the amount of cooling water is reduced by simplifying the piping, the electronic device including the server board can be reduced in weight.

It is a top view which shows typically one Example of this invention. It is typical sectional drawing which follows the II-II line | wire of FIG. It is typical sectional drawing which shows one DIMM and a pair of heat receiving plate located on both sides of the DIMM, a heat-transfer panel, and an elastic panel. It is a perspective view which shows an example of an elastic deformation part. It is sectional drawing of the block for heat transfer. It is a fragmentary top view which shows typically the example which connected heat receiving plates with the 3rd heat pipe.

  Hereinafter, an embodiment in which a server board 3 including two arithmetic elements (CPU) 1 and a plurality of memory boards (DIMM: Dual Inline Memory Module) 2 is water-cooled as a water-cooling structure according to the present invention will be described. To do. FIG. 1 is a schematic plan view, in which two cold plates 4 for cooling the CPU 1 are arranged at positions corresponding to the CPU 1 respectively, and two cooling units for cooling a plurality of DIMMs 2 at a time. 5 are arranged on both sides of the cold plate 4.

  As shown in FIG. 2, the CPU 1 is mounted on the server board 3, and a heat spreader (IHS: Integrated Heat Spreader) 6 is mounted on the upper side of the CPU 1. The cold plate 4 is disposed so as to be in close contact with the upper surface of the IHS 6. The cold plate 4 is configured to circulate the cooling water 7 inside the thin plate container.

  As shown in FIG. 2, the cold plate 4 includes a base plate 8 and a cover 9 attached to the upper surface of the base plate 8, and the lower surface of the base plate 8 is a heat receiving surface to which the heat of the CPU 1 is transmitted. Inside the hollow portion formed by the base plate 8 and the cover 9, a large number of fins 10 arranged in parallel to each other with a slight gap are provided, and a gap between these fins 10 flows. Road 11 is formed. Both end portions of the fins 10 are separated from the inner surface of the cover 9 and the space portions are header portions 12a and 12b. Each channel 11 communicates with these header portions 12a and 12b. The cover 9 is formed with an inflow port 13a that opens to one header portion 12a and an outflow port 13b that opens to the other header portion 12b. A water supply pipe 14 is connected to an inflow port 13a in one cold plate 4 shown in the lower side of FIG. 1, and an outflow port 13b in the one cold plate 4 and the other cold plate shown in the upper side of FIG. An inflow port 13 a in the plate 4 is connected by a communication pipe 15. Further, a drain pipe 16 is connected to the outflow port 13b in the other cold plate 4. The water supply pipe 14 and the drain pipe 16 are connected to a heat radiating section such as a cooling tower (not shown), and are configured to carry the heat of the cold plate 4 by the cooling water 7 and radiate the heat to the outside.

  The DIMM 2 in each cooling unit 5 is configured by mounting a plurality of memories 2B on both sides of the substrate 2A, and is inserted into a socket 17 on the server board 3 in a replaceable manner as shown in FIG. Heat receiving plates 18 are arranged in parallel to the DIMM 2 on both sides of the DIMM 2 inserted into the socket 17. This heat receiving plate 18 is for cooling the DIMM 2 and is a thin plate formed of a metal having high thermal conductivity such as copper. In the example shown in FIG. 1, the rectangular shape is long in the vertical direction of FIG. (Rectangular shape). A first heat pipe 19 is attached to one surface of each heat receiving plate 18 so that heat can be transferred.

  The first heat pipe 19 is a known heat pipe in which a working fluid such as water is sealed inside a copper pipe, for example, and an intermediate portion thereof is crushed into a thin plate shape to form a flat portion 19a. On the other hand, a groove 20 is formed on the side surface of the heat receiving plate 18 over the entire length in the longitudinal direction. The first heat pipe 19 is attached to the heat receiving plate 18 by fitting the flat portion 19 a into the groove 20 of the heat receiving plate 18. As a result, the area where the first heat pipe 19 and the heat receiving plate 18 are in direct contact with each other is widened. The flat portion 19a is fitted into the groove 20 so as not to protrude from the groove 20, and is fixed to the heat receiving plate 18 by joining means such as brazing or soldering. Therefore, the surface of the heat receiving plate 18 is flat even if the flat portion 19a is attached. In addition, it is preferable that the attachment position of the 1st heat pipe 19 (flat part 19a) with respect to the heat receiving plate 18 is an upper end side in which the temperature tends to become high among the heat receiving plates 18.

  A heat transfer panel 21 for promoting heat transfer from the DIMM 2 to the heat receiving plate 18 is provided. Two heat transfer panels 21 are provided for one DIMM 2 so as to sandwich one DIMM 2 from both sides. The heat transfer panel 21 is made of a metal having excellent heat conductivity, and is a thin plate made of, for example, aluminum or an alloy thereof. The heat transfer panel 21 is formed so as to be in contact with the entire surface of the DIMM 2 or the entire memory surface of the DIMM 2, and is configured to be brought into close contact with the surface of the DIMM 2 or the memory surface of the DIMM 2 by elastic force. Yes. Specifically, the heat transfer panel 21 is attached to the inner surface of the branching and opposing portion of the elastic panel 22 configured in a bifurcated shape.

  The elastic panel 22 is a member mainly for holding the heat transfer panel 21 and for bringing the heat transfer panel 21 into close contact with the DIMM 2 and is made of an appropriate metal. Moreover, it is comprised so that the elastic force which makes the part branched in the forked shape mutually approach may be produced. The interval between the bifurcated portions (the interval between the outer surfaces of the bifurcated portions) is equal to or greater than the interval between the heat receiving plates 18 (the interval between the opposed surfaces of the heat receiving plate 18). Yes. FIG. 4 schematically shows an example of a configuration for generating the elastic force. In the elastic panel 22, two narrow cuts are made in a portion facing the heat receiving plate 18 to form an elastic deformation portion. 23 is formed. The elastic deformation portion 23 is a portion where the elastic panel 22 is cut and raised by the above-described two cuts, and is formed to bend and protrude toward the heat receiving plate 18 side or protrude in an arc shape. The part which is present is configured to bend elastically. In the example shown in FIG. 4, the upper side is a free end, and the part below the bent part is longer than the part above the bent part. This is to facilitate insertion and removal of the elastic panel 22 between the heat receiving plates 18. The elastic panel 22 may have the same length (or width) as that of the heat transfer panel 21 or may be formed in a strip shape that is narrower than the length of the heat transfer panel 21 and has a narrow width. When formed in a strip shape, a plurality of elastic panels 22 are used for the pair of heat transfer panels 21. Therefore, when the elastic panel 22 is inserted between the heat receiving plates 18, the elastic deformation portion 23 is pushed back into the elastic panel 22 by the heat receiving plate 18, and the surface of the elastic panel 22 becomes flat, and the elastic panel 22 and the heat receiving plate 18 are in close contact with each other so that no gap is generated.

  Both end portions of the first heat pipe 19 extend from both end portions in the longitudinal direction of the heat receiving plate 18. In addition, heat transfer blocks 24 are arranged on both ends of the heat receiving plate 18 in a direction orthogonal to the heat receiving plate 18. The heat transfer block 24 is a metal block with a rectangular cross section having a length of about the width of each cooling unit 5 (the arrangement length of the heat receiving plates 18 in each cooling unit 5). As shown in FIG. 5, insertion holes 25 having the same number as the number of one heat pipe 19 and the same interval (same pitch) are formed in the vertical direction. In each insertion hole 25, the end of the first heat pipe 19 is inserted from the lower side and is closely fitted. That is, both end portions of the first heat pipe 19 are connected to the heat transfer blocks 24 arranged on the respective end portions so as to be able to transfer heat. A heat transfer material such as thermal grease may be interposed between the inner peripheral surface of the insertion hole 25 and the outer peripheral surfaces at both ends of the first heat pipe 19.

  A second heat pipe 26 is provided between each heat transfer block 24 and the cold plate 4 at a position close to each heat transfer block 24. The second heat pipe 26 is a heat transfer element or heat transport member having the same configuration as the first heat pipe 19 described above, and is configured to transfer heat between the heat transfer block 24 and the cold plate 4. ing. More specifically, two second heat pipes 26 are provided for one heat transfer block 24. As shown in FIG. 5, the end portions of the two second heat pipes 26 on the heat transfer block 24 side are crushed into a thin plate shape to form a flat portion 26a. The end portion of the second heat pipe 26 which is the flat portion 26a corresponds to the “other end portion” in the present invention.

  As shown in FIG. 5, the flat portions 26a of the two second heat pipes 26 for one heat transfer block 24 are arranged with the heat transfer block 24 interposed therebetween, and the heat transfer block. It is fixed in close contact with the surface of 24. Accordingly, since the second heat pipe 26 is in close contact with the heat transfer block 24 over a wide area, the heat transfer area between the second heat pipe 26 and the heat transfer block 24 is wide, and the thermal resistance between the two is small. It has become. In the example shown in FIG. 5, the portions on both sides and the lower side of the heat transfer block 24 recede in the thickness direction so that a space portion having a shape substantially similar to the cross-sectional shape of the flat portion 26 a is generated. A flat portion 26a having a cross-sectional shape almost the same as the cross-sectional shape of the space portion is fitted into the retreated space portion, and is fixed by means such as brazing or soldering. Therefore, the heat transfer block 24 and the flat portion 26a as a whole are configured in a simple rectangular cross-sectional shape in which no protrusion is generated.

  The two second heat pipes 26 are curved in a parallel state and extend toward the cold plate 4 side. In the configuration shown in FIG. 1, the left and right thermoelectric transmission blocks 24 in FIG. 1 are connected to the upper cold plate 4 in FIG. 1 by two second heat pipes 26, respectively. Further, the left and right heat transfer blocks 24 on the lower side of FIG. 1 are connected to the cold plate 4 on the lower side of FIG. 1 by two second heat pipes 26, respectively. And the edge part by the side of the cold plate 4 is formed in flat shape. On the other hand, as shown in FIG. 2, a groove 27 is formed on the upper surface side of the cold plate 4, and a flat end portion of the second heat pipe 26 is fitted into the groove 27 and fixed. . As a result, the heat transfer area between the second heat pipe 26 and the cold plate 4 is widened, and the thermal resistance between the two is reduced. The means for fixing the end of the second heat pipe 26 to the cold plate 4 may be brazing or soldering, or a fixing plate is screwed to the upper surface of the cold plate 4 and the fixing plate is fixed. Thus, the end of the second heat pipe 26 may be pressed into the upper surface of the cold plate 4 or the inside of the groove 27 and fixed. When such a fixed plate is used, not only heat is directly transferred from the second heat pipe 26 to the cold plate 4, but also heat is transferred from the second heat pipe 26 to the cold plate 4 through the fixed plate. Therefore, the area (heat transfer area) used for heat transfer between the second heat pipe 26 and the cold plate 4 increases, and the thermal resistance between them can be reduced.

  The cold plate 4, the heat receiving plate 18 or the heat transfer block 24 described above is directly attached to the server board 3, attached to the server board 3 by an appropriate retainer (not shown), or attached to an appropriate frame member (not shown). It may be done.

  Next, the operation of the water cooling structure will be described. The CPU 1 is brought into close contact with the lower surface of the cold plate 4 via the IHS 6. The DIMM 2 is inserted between the heat receiving plates 18 and is fitted into the socket 17. Furthermore, the elastic panel 22 is put on each DIMM 2 so as to straddle each DIMM 2, whereby the heat transfer panel 21 attached to the elastic panel 22 is inserted between the DIMM 2 and the heat receiving plate 18. The elastic panel 22 is formed with the elastic deformation portion 23 described above, and the elastic deformation portion 23 is pushed and deformed by the heat receiving plate 18, so that the heat transfer panel 21 is deformed by the elastic force of the elastic deformation portion 23. It is pressed against and comes into close contact. When the DIMM 2 is mounted on the server board 3 or replaced in this way, there is no pipe for water cooling in the vicinity of the heat receiving plate 18 or the socket 17 and there is a space so that the DIMM 2 can be mounted or replaced. Since there are almost no obstacles, the workability of installing or replacing the DIMM 2 is improved. Similarly, workability for attaching / detaching the heat transfer panel 21 or the elastic panel 22 is improved.

  On the other hand, the cooling water 7 is supplied into the cold plate 4 through the water supply pipe 14 and drained through the drain pipe 16. Inside the cold plate 4, the cooling water 7 flows through the flow path 11 described above, and heat exchange occurs between the cooling water 7 and the cold plate 4. That is, the cold plate 4 is cooled by the cooling water 7. Since the CPU 1 is in contact with the cold plate 4 via the IHS 6, the heat of the CPU 1 is transmitted to the cooling water 7 via the IHS 6 and the cold plate 4, and is carried away by the cooling water 7. That is, the CPU 1 is indirectly water cooled.

  The memory element operates in the DIMM 2 to generate heat, and the heat is transmitted to the heat receiving plate 18 through the heat transfer panel 21 and the elastic panel 22. Since the flat portion 19a that is an intermediate portion of the first heat pipe 19 is in close contact with the heat receiving plate 18, the first heat pipe 19 operates with the flat portion 19a serving as a heating portion (or an evaporation portion), The working fluid sealed in evaporates in the flat portion 19a, and the working fluid vapor flows toward both ends functioning as a heat radiating portion (or condensing portion). That is, the heat of the heat receiving plate 18 is transported to the heat transfer block 24. A second heat pipe 26 is provided between the heat transfer block 24 and the above-described cold plate 4. The heat of the heat transfer block 24 is carried by the second heat pipe 26 to the cold plate 4. The heat transfer block 24 is indirectly water-cooled by the cooling water 7 flowing in the interior. Therefore, the heat carried to the heat transfer block 24 by the first heat pipe 19 is carried to the cold plate 4 by the second heat pipe 26 and carried outside by the cooling water 7. That is, the DIMM 2 is cooled by the cooling water 7 indirectly through the heat transfer panel 21, the elastic panel 22, the heat receiving plate 18, the first heat pipe 19, the heat transfer block 24, the second heat pipe 26, and the cold plate 4. Is done. Therefore, the first heat pipe 19 and the second heat pipe 26 in the above embodiment correspond to the “heat pipe” in the invention of claim 1.

  In the embodiment described above, the cooling object is the plurality of DIMMs 2 divided into the two CPUs 1 and the two cooling units 5, whereas the place where the cooling water 7 is supplied and discharged is only the cold plate 4. Therefore, the number of piping for the cooling water 7 is reduced, the overall configuration is simplified, and accordingly, the DIMM 2 can be easily replaced as described above. In addition, since the flow location and flow rate of the cooling water 7 are reduced, the weight of the electronic device such as the server board 3 or the server rack can be reduced.

  The present invention only needs to be configured so that the DIMM 2 is indirectly water-cooled by transferring the heat of the DIMM 2 from the heat receiving plate 18 to the cold plate 4 through the heat pipe. Therefore, in the present invention, a configuration in which the heat pipe connected to the heat receiving plate 18 is directly connected to the cold plate 4 without using the heat transfer block 24 described above may be used. In that case, if each heat pipe connected to each heat receiving plate 18 is extended to the cold plate 4 and connected to the cold plate 4, the heat pipe may be complicated. In order to avoid this, for example, as shown in FIG. 6, the heat receiving plates 18 adjacent to each other are connected to each other by the heat pipe 28 corresponding to the third heat pipe in the present invention so as to be able to transfer heat. Any one of the above is preferably connected to the cold plate 4 by another heat pipe 29. With such a configuration, since the number of heat pipes extending to the cold plate 4 is reduced, the configuration can be simplified.

  In addition, the present invention is not limited to the above-described embodiment, and a configuration in which one cooling unit 5 is connected to one cold plate 4, or three or more cooling units 5 are one or three or more cold plates. 4 may be connected. Further, in the present invention, the heat receiving plate 18 may be directly adhered to the DIMM 2 without interposing the heat transfer panel 21 or the elastic panel 22 between the heat receiving plate 18 and the DIMM 2. In addition, the heat transfer block according to the present invention only needs to be connected to the first heat pipe and the second heat pipe so that heat can be transferred, and the end of the first heat pipe is inserted into the heat transfer block. Instead, the end of the second heat pipe may be inserted into the heat transfer block, and the end of the first heat pipe may be brought into close contact with the outer surface of the heat transfer block. And the 1st heat pipe should just be connected with the block for heat transmission at least one edge part.

  DESCRIPTION OF SYMBOLS 1 ... Operation element (CPU), 2 ... Memory board (DIMM: Dual Inline Memory Module), 3 ... Server board, 4 ... Cold plate, 5 ... Cooling unit, 6 ... Heat-spreading plate (IHS: Integrated Heat Spreader), 7 ... Cooling water, 11 ... flow path, 14 ... water supply pipe, 15 ... communication pipe, 16 ... drainage pipe, 17 ... socket, 18 ... heat receiving plate, 19 ... first heat pipe, 19a ... flat part, 20 ... groove, 21 ... Heat transfer panel, 22 ... Elastic panel, 23 ... Elastic deformation part, 24 ... Heat transfer block, 25 ... Insertion hole, 26 ... Second heat pipe, 26a ... Flat part, 27 ... Groove, 28 ... Heat pipe, 29 ... Other heat pipes.

Claims (7)

In the water cooling structure of the server board that cools the server board on which the arithmetic element and the plurality of memory boards to which the storage element is mounted are mounted with cooling water,
A plurality of heat receiving plates disposed between the memory boards and to which heat is transferred from the memory boards;
A heat pipe connected to the heat receiving plate;
A cold plate in which the arithmetic element is brought into contact so as to be able to transfer heat and heat is transferred from the heat receiving plate via the heat pipe;
A flow path formed inside the cold plate and through which cooling water flows ,
The heat pipe includes a first heat pipe connected to the heat receiving plate, and a second heat pipe connected to the cold plate so that one end thereof can transfer heat,
A heat transfer block in which at least one end of the first heat pipe and the other end of the second heat pipe are connected;
One of the at least one end of the first heat pipe connected to the heat transfer block and the other end of the second heat pipe connected to the heat transfer block The end is inserted into the heat transfer block; and
The other end connected to the heat transfer block is formed into a thin flat plate portion and is in close contact with the outer surface of the heat transfer block . Water cooling structure. In the water cooling structure of the server board that cools the server board on which the arithmetic element and the plurality of memory boards to which the storage element is mounted are mounted with cooling water,
A plurality of heat receiving plates disposed between the memory boards and to which heat is transferred from the memory boards;
A heat pipe connected to the heat receiving plate;
A cold plate in which the arithmetic element is brought into contact so as to be able to transfer heat and heat is transferred from the heat receiving plate via the heat pipe;
A flow path formed inside the cold plate and through which cooling water flows ,
The heat pipe includes a first heat pipe connected to the heat receiving plate, and a second heat pipe connected to the cold plate so that one end thereof can transfer heat,
A heat transfer block in which at least one end of the first heat pipe and the other end of the second heat pipe are connected;
The one end of the second heat pipe is shaped flat, and
The one end portion of the flat second heat pipe is fitted into a groove formed on the outer surface of the cold plate and is connected to the cold plate so as to be able to transfer heat. Server board water cooling structure. The one end of the second heat pipe is formed into a flat shape, and the one end of the flat second heat pipe is fitted into a groove formed on the outer surface of the cold plate. The server board water cooling structure according to claim 1 , wherein the server board is connected to the cold plate so as to be capable of transferring heat. The first heat pipe has a thin flat portion,
The flat portion is, in any one of claims 1 to 3, characterized in that it is linked to the heat transmitted to the heat receiving plate is fitted to the heat receiving plate so as not to protrude from the surface of the heat-receiving plate The water cooling structure of the described server board. The heat receiving plate is disposed on both sides of the memory board with a predetermined one piece of the memory board interposed therebetween,
Server board according to any one of claims 1 to 3, characterized by further comprising a heat pipe for heat transfer to said heat receiving plate of both sides of the single memory board connecting to a heat-transferable Water cooling structure. The server board water cooling structure according to any one of claims 1 to 5 , further comprising a heat transfer panel inserted between the heat receiving plate and the memory board to be in close contact with the memory board. . The server board water cooling structure according to claim 6 , further comprising an elastic panel inserted between the heat transfer panel and the heat receiving plate to approach the heat transfer panel toward the memory board. .

Images