Specialized computer systems for arcade games (termed"arcade game computers"or "arcade game engines") have been in production since the 1970's. Such systems were used to support the graphics and I/O demands of video arcade games which, even in those days, were relatively sophisticated compared to those supported by a general purpose personal computer.

The typical arcade game computer includes a microprocessor, RAM, a graphics interface, a mass storage device such as a hard disk, a power supply, and I/O interfaces to devices such as a joystick, a steering wheel, and push buttons. Such arcade game computers sometimes include network interfaces to a local area network (LAN). Additional digital storage may be provided with an optical disk drive, a CD-ROM drive, laser disk drive or DVD drive. Furthermore, arcade game computers may include a floppy disk drive for use by service personnel for loading test and diagnostic programs. In some circumstances, portions of an arcade game or an entire arcade game may be stored on the hard disk, CD-ROM, etc.

Arcade game systems rarely reached production volumes comparable to more standardized computer systems such as personal computers. The difference in production volumes has resulted in standardized computer systems (and their components) being less costly yet of equal or better quality than that found in older arcade game systems.

Standardized mass-produced computer enclosures are readily available for housing such mass-produced systems components. As will be appreciated a number of external form factors exist including rack-mounted enclosures, desktop enclosures and tower enclosures. However, these standardized computer enclosures were not designed for installation in arcade games.

For example, a standard computer enclosure possesses sockets and access ports on both its front and back sides. This poses a problem due to the nature of the cabinets used in most i

arcade games which typically include a door provided on the back, side, or center-mount (for motorcycle type games) of the cabinet for access to internal components (including the arcade game computer) of the arcade game. Since the arcade game computer can typically only be accessed through the cabinet door, only one side of the computer can be accessed without removing the computer from the arcade game cabinet.

Further, arcade game computers are subject to substantial amounts of mechanical vibration within the arcade game cabinet due to enthusiastic play of the game by customers.

Most computer systems include"plug-in"cards which engage with sockets or"slots"provided on the microcomputer motherboard. Standard computer enclosures possess limited mechanisms by which such plug-in cards can be secured from"walking out"of correct electrical contact with their sockets. Sensitivity to this vibration decreases the Mean Time Between Failure, which increases the frequency at which the arcade game computer needs repair, thereby increasing maintenance costs.

Standard computer enclosures and the motherboards housed within the enclosures are typically provided with a number of input/output (I/O) connectors which are not mechanically secured against the effects of vibration. Examples of such connectors include essentially cylindrical connectors for keyboard, mouse and audio connectors, as well as rectangular connectors for Universal Serial Bus (USB) lines. The vibration found in arcade games is again problematic in that the vibration may cause the connectors to at least partially disengage from their sockets.

There are some computer enclosures and computer systems built for extreme conditions, such as for military, expeditionary, or harsh manufacturing environments. Such systems are sometimes referred to as"ruggedized"systems, and often possess extra stiffening mechanisms, such as bars or angle pieces rigidly attached to top edges of plug-in cards. These bars or angle pieces are usually permanently affixed on the plug-in cards at time of manufacture and are individually provided for each card.

Arcade game computers are often installed in arcade game cabinets which possess limited air flow capabilities. Overheating of the computers can therefore be a problem. Since standard arcade game computers tend to have their fronts facing the cabinet door, and since such standard

arcade game computers usually have their fans blowing out of the back, the exhaust from the fans typically flow into the interior of the cabinet before exiting from some vent or hole. This increases the overall heat within the arcade cabinet, and therefore within the arcade game computer itself.

What is needed is a computer enclosure for an arcade game computer that is able to support service access from one side for all regular maintenance activities. What is further needed is a computer enclosure for an arcade game computer that is able to support standard, mass-produced system components in a mechanically secure and cost effective manner in situations subject to significant mechanical vibration. What is still further needed is a computer enclosure for an arcade game computer that is which can be properly cooled to ensure the proper operation of the computer.

Summary of the Invention An arcade computer system of the present invention is designed with the arcade game environment in mind. Virtually all of the access ports to the computer are provided proximate to the front face of the computer so that the computer does not have to be removed from the arcade game cabinet for servicing. Air is drawn from the rear of the computer and is expelled from the front of the computer (which is typically at the back of the arcade game cabinet), which keeps the computer and the game cabinet interior relatively cool. The air flow within the enclosure of the computer is split into multiple paths to increase the cooling efficiency of the airflow. Plugs engaged with sockets at the front of the computer may be secured against vibration with a connector mount. Plug-in cards can be secured against vibration with one or more card brackets.

More particularly, a computer system of the present invention includes an enclosure having a top, a bottom, a front side, and a plurality of additional sides. A motherboard including a microprocessor and at least one socket for a plug-in card is disposed in the enclosure. A mass storage device is also enclosed within the enclosure in communication with the microprocessor.

A plug-in card is engaged with the socket such that it can be accessed from the front side. At least one I/O socket is provided on the front side in communication with the microprocessor. A fan system is disposed within the enclosure for directing air about the mass storage device, the plug-in card, and the microprocessor along at least two flow paths.

Preferably, the fan system includes at least one fan drawing air from a rear side of said enclosure into said enclosure for exiting from said front side of said enclosure. Also preferably, the computer system includes a fan expelling air from a front side of said enclosure.

The computer system preferably also includes a retention bracket which simultaneously engages upper edges of a plurality of said plug-in cards to hold said plug-in cards in their respective sockets. One retention bracket can engage all of the plug-in cards, while a second retention bracket can engage only the long plug-in cards. The computer system also preferably includes a connector mount attached to said enclosure proximate to said I/O socket. A connector engaging said I/O socket and said connector mount is thereby kept from disengaging from said socket due to vibration.

A method for operating a computer system in accordance with the present invention includes drawing air from a rear side of an enclosure; splitting said air into multiple flow paths; directing said multiple flow paths over heat generating components of said computer system; and expelling said air from a front side of said enclosure. Preferably, essentially all of the access ports to said computer system are proximate said front side of said computer system. The method further preferably includes securing a plug in at least one access port of said computer against vibration and simultaneously securing a plurality of plug-in cards of said computer against vibration.

A computer system that addresses the specific problems of the arcade game environment is therefore provided by the present invention. The computer is vibration resistant, and is provided with superior cooling capabilities. The computer furthermore has virtually all of its access ports easily accessible for servicing without removing the computer from the arcade game cabinet.

These and other advantages will become apparent upon a study of the following descriptions and the appended drawings which illustrate several preferred embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 is a perspective view an arcade game computer in accordance with the present invention with its top cover removed; FIGURE 2 is a front elevational view of the arcade game computer of Fig. 1; FIGURE 3 is a rear elevational view of the arcade game computer of Fig. 1; FIGURE 4A is a top view plan view of the arcade game computer of Fig. 1 illustrating various components and various air flow paths through the components; FIGURE 4B is a top view plan view similar to that of Fig. 4A but illustrating various components and alternative air flow paths through the components; FIGURE SA is a perspective view of a plug mount of one preferred embodiment of the invention; FIGURE 5B is a perspective view of a cylindrical plug attached to the plug mount of Fig.

5A; FIGURE 5C is a side view of a plug and an alternative plug mount in accordance with the present invention; FIGURE 6A is a perspective view of a retention bracket for the plug-in cards according to one preferred embodiment of the invention.

FIGURE 6B is a top view of one preferred embodiment of the invention showing a collection of plug-in cards retained by two of the retention brackets of Fig. 6A; FIGURE 6C is a side view of the plug-in cards and brackets of Fig. 6B; and FIGURE 7 illustrates a fan enclosure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGURE 1 is a perspective view of a preferred embodiment of an arcade game computer 1 with the top cover (not shown, but a standard component) removed. A front side 2 of the computer 1 includes an air outlet duct 4, a power supply electrical socket 6, a power supply voltage switch 8, and power supply on/off switch 10.

A mass storage enclosure 36 is preferably located near a power supply 38. In one preferred embodiment of the invention, the mass storage enclosure 36 contains an optical disk drive 12 and a floppy disk drive 14. Preferred optical disk drives 12 include but are not limited to CD ROM drives, laser disk drives and DVD drives. The optical disk drive may further be preferred to be a removable optical disk drive. It may further preferably contain one or more hard disk drives, which can further provide high speed mass storage in which arcade games or portions of arcade games may be stored as well as accounting and other information accumulated. The removable optical disk drive 12 and the floppy disk drive 14 are accessed from the front side 2 of the arcade game computer 1.

One or more connectors 16 (having an associated plug can be screwed down) and connectors 18 and 20 (having associated plugs cannot ordinarily be screwed down) are also provided at front side 2. Connectors 18 and 20 are preferably provided connector mounts 22 and 24 of the present invention, respectively, to retain the plugs in their sockets ("connectors"). Tie- downs are used in one preferred embodiment to securely engage the associated plugs when inserted into their connectors. Other mechanisms besides tie-downs may be preferably employed in other embodiments to rigidly engage the plugs to their associated connectors, including but not limited to screw-down clamps. Such mounts will be discussed in greater detail in figures 5A to 5C below. Connector 18 is a cylindrical or"circular"connector such as an audio output connector. Connector 20 is an essentially"rectangular"connector, in one preferred embodiment, a Universal Serial Bus (USB) connector.

Other connectors 26 and 28 are preferably present on the front side 2, and may or may not be provided with mounts. Such connectors include but are not limited to keyboard, mouse, as well as audio input connectors. Other preferred embodiments of the current invention possess different combinations of presented connectors with mounts to rigidly engage the associated plugs to minimize the effects of mechanical vibration, including embodiments in which all connectors without inherent tie-down mechanisms such as side screws possess mounts to rigidly engage their associated plugs when inserted in their associated connectors.

Air flow outlet 30 is preferably formed in the front side 2 above the socket sites for plug- in cards. Access ports 40 for multiple plug-in cards engaged with sockets 42 are further preferably formed in the front side 2 below air flow outlet duct 30. Covered access ports 32 for socket sites show plug-in card side sockets further possessing connectors providing an I/O access to the internal microprocessor and associated circuitry. The sockets 42 can be seen through the vacant access ports 40 mounted on motherboard 106.

In one preferred embodiment of the invention, plug-in card 44 utilizing a covered access port 32 mechanically engages retention brackets 46 and 48. Retention brackets 46 and 48 provide a resilient pressure upon plug-in card 44 toward its socket 42 to minimize the negative effects of mechanical vibration upon the electrical interconnection of the plug-in card 44 with its socket 42. Retention brackets 46 and 48 each preferably possess engaging mechanisms 68 and 70 by which they are pressed toward sockets 42. Engaging mechanisms 68 preferably attach to mounts placed on or formed from the side of mass storage enclosure 36. Engaging mechanisms 70 preferably attach to mounts placed on or formed from the right side 74 of the enclosure. In certain preferred embodiments of the invention, screws are employed as the engaged mechanisms 68 and 70. In other preferred embodiments, nuts and bolts or screws with locking washers may be preferred as engaging mechanisms 68 and 70. These examples are provided by way of illustration and are not meant to limit the scope of the invention.

A fan enclosure 50 is preferably attached to a back side 52 of the enclosure. Such a fan enclosure can support at least one fan 54 providing an air inlet feed into the interior of the enclosure. In a further preferred embodiment, the fan enclosure 50 supports a second fan 56.

Fan 56 preferably provides an additional air inlet feed into the interior of the enclosure, which is preferably split into two or more air flow paths. One air flow path preferably flows directly into

the interior of the enclosure in an essentially perpendicular direction to the back side 52. A second preferred air flow path is parallel to the back side 52. This second preferred air flow is caused by the air flow from fan 56 deflecting off a partial covering 58 of fan 56's face and fan enclosure 50's side 64 being formed to provide minimal resistance to such an air flow.

A second mass storage enclosure 60 is preferably mounted on right side 62 on an assembly. The assembly preferably includes a sheet metal rectangular arch 90 with standoffs 92.

Standoffs 92 preferably form a rectangular pattern which aligns with commonly available mounting locations on standard, high volume mass-produced hard disk storage unit. This second mass storage enclosure preferably contains at least one hard disk storage unit. In certain preferred embodiments, the mass storage enclosure 60 is further preferred to be the case of exactly one hard-disk storage unit.

The orientation of the arcade game computer with respect to an arcade game cabinet and the resulting air flow issues will now be discussed. The arcade game customers are assumed to be facing the front of the arcade game cabinet. Therefore, if the door to the cabinet is in the back of the cabinet, the back of the arcade game computer (with the fans) is installed towards the front of the arcade game cabinet with the front of the arcade game computer (with all of the switches, ports, etc.) is facing the back of the arcade game cabinet. In this fashion, the arcade game computer can be accessed through the door of the cabinet without having to remove the arcade game computer from the cabinet. The air flow of the arcade game computer brings air in from the back of the computer enclosure, distributes the air flow through the enclosure, and forces the air out through the front of the enclosure of the arcade game computer. Therefore, air is drawn from within the cabinet of the arcade game and directed out of the back of the cabinet to reduce heat build-up within the cabinet. The flow path of the air through the enclosure of the arcade game computer is designed to efficiently remove heat from the largest heat-generating components of the computer.

FIGURE 2 is a front elevational view of the arcade game computer of Fig. 1. The front side 2 preferably includes an exhaust fan outlet 4 for a power supply 38, power supply socket 6, a voltage select switch 8, and power supply on/off switch 10. The front side 2 also supports a front face of a removable optical disk drive 12 and a floppy disk drive 14. Preferably, optical disk drives include, but are not limited to, CD-ROM drives, laser disk drives and DVD drives.

The front side 2 further supports one or more connectors 16 whose associated plug may be screwed down and connectors 18 and 20, whose associated plugs cannot ordinarily be screwed down. Connectors 18 and 20 are further preferably provided connector mounts 22 and 24, respectively, of the present invention to rigidly engage plugs inserted into their associated connectors. Tie-downs are used in one preferred embodiment to securely engage the associated plugs when inserted into their connectors. Other mechanisms besides tie-downs may be preferably employed in other embodiments to rigidly engage the plugs to their associated connectors, including but not limited to screw-down clamps. Such mounts will be discussed in greater detail in figures SA to 5C below. Connector 18 is a circular connector, such as an audio output connector. Connector 20 is an essentially rectangular connector, such as a Universal Serial Bus (USB) connector.

Other connectors 26 and 28 are preferably present with sites on the front side 2, but without corresponding mounts. Such connectors may include keyboard, mouse, as well as audio input connectors. Other preferred embodiments possess different combinations of presented connectors with mounts to rigidly engage the associated plugs to minimize the effects of mechanical vibration. Certain preferred embodiments provide, for all presented connectors without inherent tie-down mechanisms, mounts to rigidly engage their associated plugs when inserted in their associated connectors.

Air flow outlet duct 30 is preferably formed in the front side 2 above the socket sites for plug-in cards. Access ports 40 for multiple plug-in cards engaged with sockets 42 are further preferably formed in the front side 2 below air flow outlet duct 30. Covered access ports 32 for socket sites show plug-in card side sockets further possessing connectors providing an I/O access to the internal microprocessor and associated circuitry. Covered access ports 34 for socket sites show plug-in card side sockets lacking additional sockets for I/O access, or alternatively, sheet metal covers 34 used to cover access ports when there is no plug-in card engaged in the plug-in card socket.

Covered access ports 32 for socket sites show plug-in card side sockets further possessing connectors providing an I/O access to the internal microprocessor and associated circuitry. The sockets 42 can be seen through the vacant access ports 40 in Fig. 1. In a further preferred embodiment, special access port 94 shows a specialized connector which interfaces to a

specialized game interface plug-in card 96, which is not visible in this figure, but can be seen in figures 4A and 4B.

FIGURE 3 is a rear elevational view of the arcade computer system of Fig. 1 illustrating two air inlets 66 and 98 formed in the back side 52. With additional reference to Fig. 1, the air duct 98 provides air for intake fan 54, and the air duct 66 provides air for intake fan 56.

FIGURE 4A is a top view of a preferred embodiment of the invention with the top removed showing the air flow of one preferred embodiment of the invention with a hard disk enclosure mounted on the left side. FIGURE 4B is a top view of a preferred embodiment of the invention with the top removed showing the air flow of one preferred embodiment of the invention with a hard disk enclosure mounted on the base of the enclosure. The common features of these figures will first be discussed before discussion of divergent features involved with these two preferred embodiments of the invention.

In both Figs. 4A and 4B, plug-in card 44 utilizing an access port 32 mechanically engages retention brackets 46 and 48. In a further preferred embodiment, plug-in card 44 is a video graphics card. Retention brackets 46 and 48 provide a resilient pressure upon plug-in card 44 toward its socket 42 to minimize the negative effects of mechanical vibration upon the electrical interconnection of the plug-in card 44 with its socket 42. Retention brackets 46 and 48 each preferably possess engaging mechanisms 68 and 70 by which they are pressed toward sockets 42. Engaging mechanisms 68 preferably attach to mounts placed on or formed from the side of mass storage enclosure 36. Engaging mechanisms 70 preferably attach to mounts placed on or formed from the right side 74 of the enclosure. In certain preferred embodiments of the invention, screws are employed as the engaged mechanisms 68 and 70. In other preferred embodiments, nuts and bolts or screws with locking washers may be preferred as engaging mechanisms 68 and 70. These examples are provided by way of illustration and are not meant to limit the scope of the invention.

In both Figs. 4A and 4B, a power supply 38 preferably includes a blower fan 86 which utilizes air outlet 4 on front side 2 to forcibly expel heated air from air flow paths 84 and 82 from the interior of the computer enclosure. Air flow path 80 preferably mostly originates at air inlet 98 on back side 52 forcibly drawn into the invented enclosure by fan 54, flowing perpendicular

to back side 52 and between plug-in cards inserted into plug-in card sockets 42 which are mounted on mother board 106. Air flow path 80 primarily proceeds up through the plug-in cards and out the air outlet 30 on front side 2 of the invented enclosure. Air flow path 80 also receives a partial input contribution from fan 56. Air flow path 80 also contributes in part to air flow 82 traversing the portion of the motherboard 106 which feeds fan 78. Air flow path 82 preferably originates at air inlet 66 on back side 52 forcibly drawn in to the invented enclosure by fan 56 and permitted to flow perpendicular to back side 52 by shape 58 of the enclosure 50, which only partially blocks the direct flow from fan 56. Air flow path 82 proceeds under the first mass storage enclosure 36, where it tends to feed through fan 78. Fan 78 is mounted perpendicular to the motherboard and is intended to feed air directly through the heat sink fins of the microprocessor. The air flow path 82 the proceeds into and through the body of the power supply 36, being drawn toward out take fan 86.

Air flow path 84 preferably originates at air inlet 66 on back side 52 forcibly drawn in to the invented enclosure by fan 56 and forced to flow parallel to back side 52 by shape 58, which partially blocks the direct flow from fan 56. Air flow path 84 then flows essentially between hard disk enclosure 60, its mount 90 and the side of the enclosure it is mounted on. Air flow path 84 is drawn in to power supply by 36 by out take fan 86, which pushes the heated air out through air outlet 4 on front side 2 and out of the invented computer enclosure.

In Fig. 4A, the hard disk enclosure 60 is preferably mounted on the left side 62 of the enclosure on a rectangular sheet mount 90. Preferably, hard disk enclosure 60 is further mounted on rectangular sheet metal mount 90 through a collection of standoffs 92. Further preferred embodiments include hard disk enclosure 60 being the case of a single hard disk drive. In Fig.

4B, the hard disk enclosure 60 is preferably mounted on the bottom side 104 of the enclosure.

Similar preferential mounting mechanisms as described for Fig. 4A apply here.

The multiple airflow paths comprise an important aspect of the present invention. The three main heat sources in most computer systems are the video card, the microprocessor, and the hard disk drive. The multiple air flows of the present invention ensures that each of these three components are provided with a steady flow of air to effectively remove heat. In prior art computer systems, there are often"dead spaces"within the enclosure which trap heat. This is avoided with the multiple air flow paths of the present invention. Furthermore, by pulling cool

air from the back of the computer (which corresponds to the interior of the arcade game cabinet) and blowing the heated air from the front of the computer (which corresponds to the back of the arcade game cabinet), the environment within the arcade game cabinet can be kept relatively cool, and hot air can be expelled from the rear of the arcade game.

In both Figs. 4A and 4B, a motherboard 106 is preferably mounted through standoffs upon bottom side 104. Motherboard 106 preferably contains at least one microprocessor (such as a Pentium II microprocessor sold by Intel Corporation) with heat sink, a fan mounted perpendicular to the motherboard to force air across the microprocessor heat sink, and at least one plug-in card socket 42. In further preferred embodiments, there are multiple plug-in card sockets. Plug-in card sockets 42 in one preferred embodiment of the invention include plug-in card sockets with differing numbers of electrical contacts. In further preferred embodiments, there are multiple plug-in sockets with at least some of them providing interfaces to distinct buses, further interfaced to the microprocessor mounted on the motherboard. The plug-in cards are further preferred to interface to any of all of AGP, PCI and ISA computer buses. A further preferred embodiment includes, one AGP plug-in card socket, at least one PCI plug-in card socket and at least one ISA bus plug-in card socket make up the collection of plug-in card sockets 42 on the motherboard 106.

FIGURE SA is a perspective view of a plug mount 75 of one preferred embodiment of the invention showing the adjoining region 84 of the sheet metal from which the plug mount was formed. In one preferred embodiment, a piece of sheet metal 84 is die stamped to form a connected metal strip including a platform 76 supported by a riser 78. In a further preferred embodiment of the invention, sheet metal piece 84 is die stamped to form a connected metal strip including a lip 74, a platform 76 and a riser 78. A further preferred embodiment of the invention includes forming a notch 112 on one or more sides of platform 76 which can be engaged by a tie- wrap 86 to prevent slippage. In a preferred embodiment of the invention, an elastomeric pad 82 is attached to platform 76 to provide a cushioning effect when the associated plug is rigidly engaged and the computer system experiences mechanical vibration. FIGURE 5B is a perspective view of a cylindrical plug 90 attached to the plug mount 75 by a tie-wrap 86. The tie wrap preferably engages the notch 112 to prevent slippage of the tie-wrap on the platform 76.

As long as the tie-wrap is sufficiently tightened around the plug 90 and the platform 76, the plug 90 will not move in an axial sense. Therefore, the plug 90 will remain engaged with its

associated connector despite considerable vibration and/or other mechanical shocks. The elastomeric pad 82 further holds the plug 90 in place and reduces the amount of vibration transmitted to the plug 90 through the plug mount 75.

In a preferred embodiment of the invention, the plug mount 75 is installed on the enclosure for the arcade game computer, the associated plug is inserted in a connector, and a tie wrap is affixed around the associated inserted plug and tightened, causing a rigid engagement between the plug mount and the plug which resists the negative effects of mechanical vibration.

FIGURE 5C is a side view of a cylindrical plug 90 attached to a plug mount 75'composed of a platform 76'with a lip 74', an angled riser 78', and a base 84'. An end of the base 84'is bent upwardly to form a second lip 108. This configuration is well suited to be mounted in a recessed area 109 (see Fig. 1) of the enclosure. The plug mounts 75 and 75'may be mounted to the enclosure by suitable fasteners, or may be affixed by spot welding, soldering, or the like.

FIGURE 6A is a perspective view of a retention bracket 46/48 for the plug-in cards according to one preferred embodiment of the invention. The brackets include an elongated member 89 having a base portion 90 and two downwardly extending side portions 88 and 92. An elongated, rectangular body 110 of elastomeric material (such as a foam rubber) is held partially with the member 88, such as with a suitable adhesive. A portion"P"of the material 110 extends beyond the lower edges of sides 88 and 92, and are used to resiliently engage the tops of the plug-in cards. Cylindrical openings 68 and 70 on the base portion 90 of the member 89 provide holes for screws that hold the retention brackets 46/48 firmly in place on the top edges of the plug-in cards.

FIGURE 6B is a top view of one preferred embodiment of the invention showing a collection of plug-in cards 72 and plug-in cards 44 retained by the two retention brackets 46 and 48. The retentive action upon the plug-in cards comes by applying the engaging mechanisms, such as screws through holes 68 and 70 on each retention bracket. Plug-in cards 72, which are short, are shown retained only by retention bracket 46. Plug-in cards 44, which are longer, are shown retained by both retention brackets, 46 and 48. This situation is reflected in the disposition of many motherboards, which include plug in card sockets for AGP, PCI and/or ISA

bus plug-in cards. These plug-in cards typically have mechanical mounts (not shown) below the depicted region of discourse. These plug-in cards are not all the same length. Some plug-in cards would only be retained by a single retention bracket. The longer plug-in cards would be retained by both retention brackets.

It should be noted that the depiction of two retention brackets in this and other figures within this document is not mean to limit the scope of the claimed invention. In certain preferred embodiments, a single retention bracket may be chosen. In other preferred embodiments of the invention, more than two retention brackets may be preferred.

FIGURE 6C is a side view of one preferred embodiment of the invention showing a collection of plug-in cards retained by two retention brackets 46 and 48 according to one preferred embodiment of the invention. Plug-in cards of two lengths are displayed, shorter plug- in cards 72 and longer plug-in cards 44.

The retentive action upon the plug-in cards comes by applying an engagement force on each retention bracket, of which only 68 is visible from this view. This compresses elastic material 110 providing a cushioning effect on the engaged plug-in cards when the computer system is subjected to mechanical vibration. The retaining mechanisms preferably attach to mounts or posts 111 in the side walls of adjoining elements of the enclosure, such as on the first mass storage enclosure 36 or on the inner sidewall of the enclosure.

FIGURE 7 shows the fan enclosure 50 mounted on the back side 52 of the computer enclosure according to one preferred embodiment of the invention. The fan enclosure is preferably composed of two major faces, where a first face 51 is parallel the back side 52 and includes vents 53 and 55 and an air block 58 and where a second face 64 is perpendicular to the back side 52. Face 64 of fan enclosure 50 is preferably formed so as to minimize air flow resistance for air moving essentially parallel back side 52 with the provision of an aperture 65.

The fan enclosure preferably houses two fans fed by air inlets 98 and 66, which are preferably located on the back side 52 of the enclosure. The enclosure is designed to provide the air flow through the enclosure as previously described.

While this invention has been discussed with reference to several preferred embodiments, it is contemplated that various alterations, permutations, and equivalents thereof will become apparent to those skilled in the art upon a reading of the descriptions and a study of the drawings.

It is therefore intended that the following appended claims include all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.

What is claimed is: