ANALYSIS OF EXPERIMENTAL AND SIMULATION OF NORTH BRIDGE AND PROCESSOR HEAT SINK

Transcription

1 ANALYSIS OF EXPERIMENTAL AND SIMULATION OF NORTH BRIDGE AND PROCESSOR HEAT SINK Abhinandan Jain 1, Pankaj Mishra 2, P.K Upadhyay 3 PG Scholar 1, Assistant Professor 2, Associate Professor 3 Department of Mechanical Engineering, NRI Institute of Research & Technology, Bhopal, India ABSTRACT: The appropriate operating temperature of the processor depend upon its manufacturer and processor speed where the sensor is to be found and what programs is currently running. In the present work the experimental and analytical studies were performed in order to optimize geometrical fin parameters for natural convective heat transfer from continuous and discontinuous heat sink installed at North Bridge and at CPU main processor in computer system and discontinuous heat sink proposed for geometrical and cost effective material optimization. In the present work it has been observed that the interrupted fins exhibit a thermal boundary layer interruption which helps increase the heat transfer rate. The study aspires to deal with shortcoming by investigating the effect of fin interruption on the efficiency with which the heat is transferred from the heat sink to the environment. In addition fin interruption leads to noteworthy weight reduction which can lower the manufacturing costs. In contrast adding up interruptions that reduce the heat transfer rate which decrease the total heat transfer rate from the surface area. These two opposing effects clearly indicate that an optimum fin interruption provide the maximum heat transfer rate from naturally cooled heat sink. In this paper, summarize the discontinuous heat sink has better performance and heat dissipation from the heating zone in the computer mother board. It is seen from the above analysis that only central processing unit and north bridge heat sink is generating high temperature and also central processing unit contain fan for forcing air on the heat sink connected through it. But on the North Bridge and South Bridge does not have any fan for force cooling because maximum temperature generate only on CPU socket. KEYWORDS: Heat sink, Interrupted Fins, Natural Convection, North Bridge etc. I. INTRODUCTION The heat transfer through the heat sinks present in flow channel can be increased by employing modification in passive surfaces, such as extended surfaces with geometrical modifications. These techniques are having wide application such as cooling turbine aerofoil, electronic cooling systems, biomedical instruments, and heat exchangers. The pin fin technology is widely used in many applications such as computer mother board heat sink over microprocessor. The configuration of productive cooling systems is fundamental for solid execution of high power thickness gadgets. Various disappointment systems in electronic gadgets, for example, between metallic development, metal movement, and void arrangement, are identified with thermal impacts. Truth is told, the rate of such failures about pairs with each 10 C increment over the working temperature (~80 C) of high power hardware [1]. Other than the harm that overabundance thermally can bring about, it builds the development of free electrons inside of semiconductors, creating an expansion in sign commotion [2]. Therefore, gadgets thermal administration is of critical significance as is reflected in the business sector. Thermal administration items demonstrate a development from about $7.5 billion in 2010 to $8 billion in 2011, and it is required to develop to $10.9 billion in 2016, a compound yearly development rate increment of 6.4%. Warm administration equipment, e.g. fans and thermally sinks, represents around 84% of the aggregate business sector. Other primary cooling item sections, e.g. programming, interface materials, and substrates, every record for somewhere around 4% and 6% of the business sector, separately. The North American business sector will keep up its number one position all through this period, with a piece of the overall industry of around 37%, trailed by Asia-Pacific with roughly 23% to 24% [3].This power scattering creates heat, which is a by-item in numerous designing applications. This undesirable by-item can diminish the execution of the frameworks since verging on each building framework is intended to work inside of a specific temperature limits. Overheating so as to surpass these breaking points, could prompt a framework disappointment.

2 As of now, the thermal misfortunes of influence electronic gadgets are expanding. In the meantime, their sizes are diminishing. Hence, warm sinks need to scatter higher thermally fluxes in each new outline. Accordingly, conceiving proficient cooling answers for meet these difficulties is of fundamental significance and impact sly affects the execution and unwavering quality of electronic and force electronic gadgets. II. LITERNATURE REVIEW Singh, B. Ubhi., et.al. [1], they have composed and broke down the warmth exchange through blade expansion in plate balances. They learned about different geometries, for example, rectangular, trapezium, triangular, and round expansions in plate balances. The outcomes demonstrated that plate blade with augmentations gave 5% to 13% more warmth exchange than balance without expansions. The adequacy of rectangular augmentation plate balance is more than alternate sorts of expansion. S. R Pawar and R. B. Varasu [2], they have the warmth exchange by common convection from triangular scored blade exhibit. They learned about various indent geometries, for example, balance without score, blade with 20% indent with territory remuneration and balance with 40% indent with range pay as for different parameters, for example, tallness, length, score measurement, balance separating and balance thickness. The studies demonstrated that warmth exchange coefficient is lower in indented blade when contrasted with without score. There was 7% expansion in warmth exchange for 20% scored blade and 10% for 40% indent balance. The warmth exchange increments with expansion in indent size with territory remuneration. U. S. Gawai, Mathew V. K. et.al. [3], they have done exploratory examination of warmth exchange by pin balance. The outcomes for single blade of aluminum and metal were concentrated on for warmth exchange. The outcomes demonstrated that the warmth exchange coefficient and proficiency of aluminum balance was more prominent than the metal blade. D. D. Palande and Walunj et. al [4], they have done exploratory examination of grade thin plate blades heat sink under common convection. They have probed blades as for perspective proportion and distinctive radiator data wattage the outcome demonstrated that regular convection heat exchange increments with warmth information. The convective warmth exchange increments with viewpoint proportion. Hagote and Dahake et. al [5], they have improved the normal convection heat exchange coefficient by utilizing V- balance cluster. They dissected the V-balance utilizing ANSYS CFX and tentatively. They utilized plate blades where the balances were organized at a slant of 60o. The greatest convective warmth exchange got was 600. V. Karthikegn, Babu et.al. [6], they outlined and dissected the regular convection heat exchange coefficient between rectangular blade exhibit with expansion and balance cluster without augmentation. The warmth exchange through blade cluster with rectangular expansion, roundabout augmentation, trapezoidal expansion, triangular expansion, 18mm aperture, 20 mm puncturing, 22 mm aperture, 24 mm puncturing were 27.32, 25.63, 25.62, 24.68, 23.82, 23.52, 22.97, separately. The blade exhibit with rectangular expansions has least temperature toward the end of balance cluster, when contrasted with balance exhibit with rectangular augmentation, without augmentation and with aperture. M. Reddy and G. Shivashankaran et al. [7], they have done numerical recreation of constrained convection heat exchange upgrade by permeable pin balance in rectangular channel. They had learned about round, long circular and short curved pin blade heat sink by changing gulf speeds i.e. 0.5m/s, 1m/s, 1.5m/s and 2m/s utilizing ANSYS CFD familiar programming. The outcome demonstrated that the warmth move efficiencies in permeable pin balance are around half higher than strong pin balance. M. Ali, Tabassum et.al. [8], they have performed warm and water driven examination of rectangular balance exhibits with various aperture size and number. They have done analysis study by taking base range 1088 mm2. They changed puncturing from 0 to 2, and differed aperture breadth structure 0mm to 3mm. The outcomes demonstrated that warmth exchange and weight drop expanded with expansion in Reynolds number for all balances. With trials it was found that with increasingly or bigger holes the proficiency and viability expanded, though the warm resistance and weight drop diminished. K. Kumar, Vinay et.al. [9], they performed warm and auxiliary investigation of tree formed blade exhibit. They had brought tree formed blade with openings and tree molded balance without spaces for their investigation. They additionally concentrated on the impact of material on the outcomes for the same geometries by taking aluminum composite, auxiliary steel and copper combination for the same. The outcomes got demonstrated that the abilities of the opened tree balances are superior to without opened tree blades. As indicated by material the copper blades with openings was best for warmth exchange among every one of the balances. The aluminum opened blade was

3 discovered best as it has successful warmth exchange without distortion among every one of the balances taken for the study. V. Kumar and Bartaria et al.[10], they have done exploratory and CFD examination of a circular pin balance heat sink utilizing Ansys Fluent v They have done the study by changing the measurement of curved pin blade i.e. by shifting the cross-segment territory. The outcomes demonstrated that for every one of the speeds 2mm minor pivot circular pin balance would be wise to warm resistance and weight drop. III. METHODOLOGY III.1. THE MOTHERBOARD The main printed circuit board in a computer is known as the Motherboard. The motherboard acts as the connection point where major computer components are attached to. It holds many of the crucial components of the system like the processor, memory, expansion slots and connects directly or indirectly to every part of the PC. The type of motherboard installed in a PC has a great effect on system speed and expansion capabilities. III.2. CPU- CENTRAL PROCESSING UNIT The processor chip is identified by the processor type and the manufacturer; and this information is usually inscribed on the processor chip e.g. Intel 386, Advanced Micro Devices (AMD) 386, Cyrix 486, Pentium MMX, (old processor types) Intel Core 2Duo etc. III.3. MAIN MEMORY / RANDOM ACCESS MEMORY (RAM) Random access memory is volatile memory, meaning it loses its contents once power is turned off. This is different from non-volatile memory such as hard disks and flash memory, which do not require a power source to retain data. When a computer shuts down properly, all data located in random access memory is returned back to permanent storage on the hard drive or flash drive. At the next boot-up, RAM begins to fill with programs automatically loaded at startup, and with files opened by the user a process called booting. III.4. BIOS- BASIC INPUT OUTPUT SYSTEM All motherboards include a small block of Read Only Memory (ROM) which is separate from the main system memory used for loading and running software. On PCs, the BIOS contains all the code required to control the keyboard, display screen, disk drives, serial communications, and a number of miscellaneous functions. III.5. CMOS-COMPLEMENTARY METAL OXIDE SEMICONDUCTOR Motherboards also include a small separate block of memory made from CMOS RAM chips which is kept alive by a battery (known as a CMOS battery) even when the PC s power is off. This prevents reconfiguration when the PC is powered on. III.6. EXPANSION BUSES An input/output pathway from the CPU to peripheral devices typically made up of a series of slots on the motherboard. Expansion boards (cards) plug into the bus. PCI is the common expansion bus in a PC and other hardware platforms. Buses carry signals, such as data; memory addresses, power and control signals from component to component. Figure 1: Main parts of motherboard III.7. CPU CLOCK

4 The clock synchronizes the operation of all parts of the PC and provides the basic timing signal for the CPU. Using a quartz crystal, the CPU clock breathes life into the microprocessor by feeding it a constant flow of pulses. For example, a 200 MHz CPU receives 200 million pulses per second from the clock. III.8. SWITCHES AND JUMPERS DIP (Dual In-line Package) switches are small electronic switches found on the circuit board that can be turned on or off just like a normal switch. They are very small and so are usually flipped with a pointed object such as a screwdriver, bent paper clip or pen top. Care should be taken when cleaning near DIP switches as some solvents may destroy them. Figure 2: Northbridge heat sink Figure 3: CPU heat sink with copper block on bottom side of the motherboard Figure 4: CPU heat sink with copper block on fan side of the motherboard

5 Figure 5: Complete assembly of CPU Heat sink with Fan Figure 6: CPU Heat sink Figure 7: CPU Heat sink IV. RESULT AND DISCUSSION The static thermal analysis ware conducted using ANSYS workbench based on finite volume methodology the effects of different important geometrical parameters on the steady state natural convective heat transfer rate from both continuous and discontinuous fins. Experimental reading taken by thermocouple as shown in figure: as this temperature is attained in approx 30min of operation of system. When a continuous heat sink is heated the buoyancy force of surrounding air start moving and its layers of thermal boundary start to develop at the bottom edges of the opposing surfaces of the adjacent fins and the boundary layers finally come together if the fins are sufficiently long which creating a fully developed air flow [46] [A. Bejan, Convection heat transfer, Prentice Hall, 1984.]. Where the discontinuous fins disturb the thermal boundary layer growth and maintain a thermally developing flow region which is finally leads to a higher natural heat transfer coefficient. Flow of air over the discontinuous fin are showing in the following figure where temperature of air increasing as it contact with hot discontinuous heat sink in this figure we can see that if air is flow over the discontinuous fin the thermal boundary layer growth is also not continuous and flow pattern also disturb due to discontinuity of heat sink throughout the entire length ASSUMPTIONS The following assumptions are made to model the air flow and heat transfer in a continuous finned heat sink. Steady state laminar flow of air is considered Symmetric flow and identical heat transfer throughout the heat sink Isothermal boundary condition is applied for the base and fins. Air entrance from the side is Negligible on the heat sink means the fresh air inflow and outflow from the open sides of the outmost fins wall is small compared to the air flow entering from the bottom of the fins array BOUNDARY CONDITION

6 From the experimental reading it is cleare that the maximum temperature at the bottom end of the north bridge heat sink is 100 o C or K. so the apply temperature at the bottom end of the heat sink 100 o C K. Since the entaire system kept inside the metalic cabine and the air flow inside this cabine is at about at room temperature hence the value of convective coefficient lie between 10 to 100 for the present work the value of convective coefficient taken as 25 The maximum time taken to rise this temperature is takes as 1800 second as obtained from experimental reading. The solver used for this FEM analysis is Mechanical APDL solver 4.3. THERMAL ANALYSIS FOR CONTINUOUS NORTH BRIDGE HEAT SINK OF PROCESSOR Thermal analysis is a method of keeping the device junction temperature within the operating range. Since in a design the Ambient temperature & the power dissipation are fixed, only way it can control the junction temperature within operating range is by reducing the Junction to Ambient Thermal Resistance. The complete thermal analysis in the present work is follow three major steps. Preprocessor, solutions and post processor PREPROCESSING: The preprocessing involves creation of geometry; define element type, material property, meshing and boundary conditions CAD MODELING: Creation of CAD model by using ANSYS Workbench modeling tools for creating the geometry of the part or assembly to perform FEA. In the present work The CAD geometry of continuous heat sink is created on the ANSYS workbench itself since its geometry is not so complicated that is why the heat sink of Northbridge and CPU heat sink created with the help of engineering geometry tool available in ANSYS workbench. For geometry construction the length and width of North Bridge heat sink is taken as 90 mm x 63 mm, the maximum height is 33 mm, there are total 11 walls in the north bridge with different heights and the gap between two consecutive walls is 2 mm. A three dimensional view of north bridge heat sink is shown in figure No. 8 Figure 8: CAD geometry of north bridge continuous heat sink MESHING: Meshing is a critical operation in FEA. In this operation, the CAD geometry is divided into large numbers of small pieces. The small pieces are called mesh. The analysis accuracy and duration depends on the mesh size and orientations. With the increase in mesh size, the finite element analysis speed increase but the accuracy decrease. After completing the CAD geometry of heat sink is imported in ANSYS workbench for further thermal analysis and the next step is meshing. The mesh created in this work is shown in figure No.11 the total Node is generated is and total elements is , it is clear from the mesh geometry the node numbers and element numbers are almost seven in digit which show that the mesh is very fine because the result accuracy depends on the mesh quality. Figure 11: meshing of north bridge continuous heat sink (Node: , Element: )

7 DEFINING MATERIAL PROPERTIES: for any kind of analysis material property are the main things which must be defined before moving further analysis. There are thousands of materials available in the ANSYS environment and if required library is not available in ANSYS directory the new material directory can be created as per requirement. For the present work aluminium used as a material of north bridge heat sink Figure 12: Temperature distribution of north bridge continuous heat sink The above result (Figure 12) indicates the temperature distribution of north bridge continuous heat sink the maximum temperature is K and minimum temperature is K. Figure 13: Total heat flux of north bridge continuous heat sink The above result (Figure 13) indicates Total heat flux generated on the north bridge continuous heat sink maximum heat flux generated is e5 W/m2 and minimum heat flux generated is W/m2 (Heat flux or thermal flux is the rate of heat energy transfer through a given surface per unit time.) Figure 14: Directional heat flux of north bridge continuous heat sink The above result (Figure 14) indicates directional heat flux generated on the north bridge continuous heat sink maximum heat flux generated is W/m2 and minimum heat flux generated is W/m THERMAL ANALYSIS FOR DISCONTINUOUS NORTH BRIDGE HEAT SINK: The CAD geometry of discontinuous heat sink is created on the ANSYS workbench itself since its geometry is not so complicated that is why the heat sink of Northbridge and CPU heat sink created with the help of engineering geometry tool available in ANSYS workbench. For geometry construction the length and width of North Bridge heat sink is taken as 90 mm x 63 mm, the maximum height is 33 mm, there are total 17 walls in the north bridge with different heights and the gap between two consecutive walls is 2 mm. For the creation of interrupted heat sink total 10 division made with 2 mm gap A three dimensional view of north bridge heat sink is shown in figure No. 15

8 Figure 15: CAD geometry of north bridge discontinuous heat sink After completing the CAD geometry of discontinuous heat sink is imported in ANSYS workbench for further thermal analysis and the next step is meshing. The mesh created in this work is shown in figure No. 16 the total Node is generated is and total elements is , it is clear from the mesh geometry the node numbers and element numbers are almost seven in digit which show that the mesh is very fine because the result accuracy depends on the mesh quality. Figure 16: Meshing of north bridge discontinuous heat sink (Node: , Element: ) Figure 17: Temperature distribution of north bridge discontinuous heat sink The above result (Figure No. 17 ) indicates the temperature distribution of north bridge discontinuous heat sink the maximum temperature is K and minimum temperature is K. Figure 18: Total heat flux of north bridge discontinuous heat sink The above results (Figure 18) indicates Total heat flux generated on the north bridge discontinuous heat sink maximum heat flux generated is 3.756e5 W/m2 and minimum heat flux generated is W/m2 (Heat flux or thermal flux is the rate of heat energy transfer through a given surface per unit time.)

9 Figure 19: Directional Heat flux for north bridge discontinuous heat sink The above results (Figure 19) indicates directional heat flux generated on the north bridge discontinuous heat sink maximum heat flux generated is e5 W/m2 and minimum heat flux generated is e5 W/m THERMAL ANALYSIS FOR CONTINUOUS HEAT SINK OF CENTRAL PROCESSING UNIT The CAD geometry of continuous heat sink is created on the ANSYS workbench itself since its geometry is not so complicated that is why the heat sink of North Bridge and CPU heat sink created with the help of engineering geometry tool available in ANSYS workbench. For geometry construction the length and width of central processing unit heat sink is taken as 90 mm x 63 mm, the maximum height is 33 mm, there are total 17 walls in the central processing unit with different heights and the gap between two consecutive walls is 2 mm. For the creation of interrupted heat sink total 10 division made with 2 mm gap A three dimensional view of central processing unit heat sink is shown in figure No. 20 Figure 20: CAD geometry of Continuous heat sink of central processing unit After completing the CAD geometry of continuous CPU heat sink is imported in ANSYS workbench for further thermal analysis and the next step is meshing. The mesh created in this work is shown in figure No. 21 the total Node is generated is and total elements is 40716, it is clear from the mesh geometry the node numbers and element numbers are almost seven in digit which show that the mesh is very fine because the result accuracy depends on the mesh quality. Figure 21: Meshing of continuous fin for Continuous heat sink of central processing unit (Node : , Element: 40716) Figure 22: Temperature distribution of Continuous heat sink of central processing unit The above results (Figure No. 22) indicate the temperature distribution of central processing unit continuous heat sink the maximum temperature is K and minimum temperature is K.

10 Figure 23: Total heat flux of Continuous heat sink of central processing unit The above results (Figure No. 23) indicates Total heat flux generated on the central processing unit continuous heat sink maximum heat flux generated is W/m2 and minimum heat flux generated is W/m2 (Heat flux or thermal flux is the rate of heat energy transfer through a given surface per unit time.) Figure 24: Directional heat flux of Continuous heat sink of central processing unit The above results (Figure 24) indicates directional heat flux generated on the central processing unit continuous heat sink maximum heat flux generated is W/m2 and minimum heat flux generated is W/m THERMAL ANALYSIS FOR DISCONTINUOUS HEAT SINK OF CENTRAL PROCESSING UNIT The CAD geometry of discontinuous heat sink is created on the ANSYS workbench itself since its geometry is not so complicated that is why the heat sink of North Bridge and CPU heat sink created with the help of engineering geometry tool available in ANSYS workbench. For geometry construction the length and width of central processing unit heat sink is taken as 90 mm x 63 mm, the maximum height is 33 mm, there are total 17 walls in the central processing unit with different heights and the gap between two consecutive walls is 2 mm. For the creation of interrupted heat sink total 10 division made with 2 mm gap A three dimensional view of central processing unit heat sink is shown in figure No. 25 Figure 25: CAD geometry of discontinuous heat sink of central processing unit After completing the CAD geometry of discontinuous CPU heat sink is imported in ANSYS workbench for further thermal analysis and the next step is meshing. The mesh created in this work is shown in figure No. 26 the total Node is generated is and total elements is , it is clear from the mesh geometry the node numbers and element numbers are almost seven in digit which show that the mesh is very fine because the result accuracy depends on the mesh quality. Figure 26: meshing of discontinuous heat sink of central processing unit (Node: , Element: )

11 Figure 5.27: Temperature distribution of discontinuous heat sink of central processing unit The above result (Figure No. 27) indicates the temperature distribution of central processing unit discontinuous heat sink the maximum temperature is K and minimum temperature is K. Figure 28: Total heat flux of discontinuous heat sink of central processing unit The above results (Figure No. 28) indicates Total heat flux generated on the central processing unit discontinuous heat sink maximum heat flux generated is W/m2 and minimum heat flux generated is W/m2 (Heat flux or thermal flux is the rate of heat energy transfer through a given surface per unit time.) Figure 29: directional heat flux of discontinuous heat sink of central processing unit The above results (Figure 29) indicates directional heat flux generated on the central processing unit discontinuous heat sink maximum heat flux generated is W/m2 and minimum heat flux generated is W/m2 V. VALIDATION Heat flux cannot be calculated due to uneven geometry of the heat sink Formula for heat flux = ( ) Where K= thermal conductivity of material (237.5 w/mk) A= cross sectional area (L x W) m2 Thot = maximum temperature at bottom end of heat sink in degree Kelvin Tcold = atmospheric temperature in degree Kelvin t = thickness of heat sink in meter

12 Figure 30: Comparison between Temperature distribution experimental & Analytical values in North Bridge Continuous heat sink Figure 30 show the temperature distribution (K) variation on experimental and analytical reading in north bridge continuous heat sink. This graph shows the maximum temperature distributions are same in both of case but 4K difference in minimum temperature distribution. Figure 31: Comparison between Temperature distribution experimental & Analytical values in North Bridge discontinuous heat sink Figure 31 show the temperature distribution (K) variation on experimental and analytical reading in north bridge discontinuous heat sink. This graph shows the 2.4K difference in maximum temperature distributions and 6K difference in minimum temperature distribution.

13 Figure 32: Comparison between Temperature distribution experimental & Analytical values in Central Processing Unit continuous heat sink Figure 32 show the temperature distribution (K) variation on experimental and analytical reading in Central Processing Unit continuous heat sink. This graph and table shows the 5.076K difference in maximum temperature distributions and 3.36K difference in minimum temperature distribution. Figure 33: Comparison between Temperature distribution experimental & Analytical values in Central Processing Unit discontinuous heat sink

14 Figure 33 show the temperature distribution (K) variation on experimental and analytical reading in Central Processing Unit discontinuous heat sink. This graph and table shows the 3.879K difference in maximum temperature distributions and 2.804K difference in minimum temperature distribution. VI. CONCLUSION Experimental and analytical studies were performed in order to optimize geometrical fin parameters for natural convective heat transfer from continuous fins installed in our computer system and discontinuous fin proposed for geometrical and cost effective material optimization. Carefully estimating thermal resistance is important for the long-term reliability of any Integrated Circuit. Design engineers should always correlate the power consumption of the device with the maximum allowable Power dissipation of the package selected for that device using the provided thermal resistance parameters. The following points have been identified in the form of conclusive statements which are as follows. 1. Discontinuous fin maximize the total natural convective heat transfer as compared to continuous fin. 2. Due to discontinuous geometry for proposed fin is cost effective as compared to continuous fins 3. Since the maximum temperature developed on all types of fin design but the lower temperature is much below in discontinuous fin is attended. 4. In the present work two types of CPU heat sink are used for thermal analysis first one is rectangular heat sink and another one is circular. Since rectangular heat sink are checked for continuous and discontinuous heat sink from which discontinuous heat sink gives better heat convection from the heat of central processing unit. 5. The circular CPU heat sink design is safe and generating temperature on it is not serious to intense it that is why CPU heat sink is safe during the thermal analysis and there is no need to change its design. To summarize the discontinuous heat sink has better performance and heat dissipation from the heating zone in the computer mother board. It is seen from the above analysis that only central processing unit and north bridge heat sink is generating high temperature and also central processing unit contain fan for forcing air on the heat sink connected through it. But on the North Bridge and South Bridge does not have any fan for force cooling because maximum temperature generate only on CPU socket. In the experimental investigation the maximum temperature also indicating on North Bridge which was about 100oc that is why the present work more concentrate on it and also proposed new design for it only. VII. FUTURE SCOPE The present work confined only the redesign of north bridge heat sink but in future south bridge can also be considered for redesign and CPU heat sink can also. There are some possible future aspects which can be possible for further work. 1. Transient thermal analysis can be also performed on all kind of heat sink used in present work 2. CFD analysis can also be done to understand air flow around the motherboard of the computer system. 3. Apart from aluminum and copper there should be some other material may be for heat sink in computers motherboard. 4. Evaluation of thermal properties by varying the size of the heat sink. 5. It may also be possible that heat sink completely replaced by some other cooling medium which are using in refrigerator and air-conditions. REFERENCES [1] P. Singh, H. Lal, B. S. Ubhi, Design and Analysis for Heat Transfer Through Fin with Extensions, International Journal of Innovative Research in Science, Engineering and Technology, Vol.3, Issue 5, May [2] Sachin R. Pawar, R. Yadav, Computational Analysis of Heat Transfer by Natural Convection from Triangular Notched Fin Array, IJST- International Journal of Science Technology & Engineering, Vol-1, Issue 10, April [3] U. S. Gawai, Mathew V. 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