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Soft Power: ATX systems were the ones where the +5 Standby and Power On signals were introduced. These signals are used along with a change to the way the power switch works, as part of the "Soft Power" feature that enables features such as allowing the operating system to turn off the PC. .
Additional Signals: ATX defines several additional signals used for fan control, various motherboard, and more. .
Changed Motherboard Connectors: Breaking with 15 years of tradition created by the PC/XT, AT, Baby AT and LPX form factors, Intel specified new motherboard connectors for the ATX form factor. This was in part due to the additional signals used by the ATX power supply and motherboards. For compatibility, some motherboards include both the new and old style of connector. .
Modified Fan Direction and Placement: One of the goals of the original ATX specification was to change the way the power supply fan worked. At around the time ATX was introduced; cooling fans were becoming the standard for the newer, faster CPUs on the market. Instead of exhausting air out the back of the case as had always been the norm, Intel wanted to use this exhaust air to cool the processor directly, saving the cost of a cooling fan. Therefore, the ATX specification calls for the fan to run in the opposite direction and be placed near the CPU's location on the motherboard, to blow on it for cooling. .
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Optical Drives:.
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The CD-ROM (compact disc read only memory) is one of the most important components in your pc. Most software usually comes on a CD so you are out of luck if you don't have one. CD-ROM's are popular with software makers because it can hold 650 MB while a floppy can only hold 1.44 MB. The speed associated with the drives determines their transfer rate. .
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Today, CD-ROMs use SCSI or EIDE and can be installed without taking up an extra slot. Older CD-ROMs were connected to a controller card that is attached to one of the motherboard's expansion slots.
