Contents 1. Executive Summary…………………………………………………………………………………………7 2. ATX Form-factor Overview……………………………………………………………………………….8 3. Layout …………………………………………………………………………………………………………….9 3.1 Board Size……………………………………………………………………………………………………………………….. 9 3.2 Mounting Hole Placement …………………………………………………………………………………………………… 9 3.3 Connector Placement ………………………………………………………………………………………………………… 11 3.3.1 Expansion slots ……………………………………………………………………………………………………… 11 3.3.2 Power Input …………………………………………………………………………………………………………… 13 3.3.3 Disk I/O ……………………………………………………………………………………………………………….. 13 3.3.4 Front Panel I/O………………………………………………………………………………………………………. 13 3.3.5 Back Panel I/O ………………………………………………………………………………………………………. 13 3.3.6 Memory Sockets ……………………………………………………………………………………………………. 16 3.3.7 Processor ……………………………………………………………………………………………………………… 16 3.4 Height Constraints…………………………………………………………………………………………………………….. 16 3.4.1 Primary (Component) Side Height Constraints…………………………………………………………… 16 3.4.2 Secondary (Bottom/Solder) Side Height Constraints …………………………………………………… 18 4. Power Delivery ………………………………………………………………………………………………..19 4.1 Power Supply Connectors…………………………………………………………………………………………………… 19 4.1.1 Aux Power Connector for 250 W and 300 W Configurations ……………………………………….. 20 4.1.2 2×2 Connector………………………………………………………………………………………………………. 20 4.1.3 Power Signal Control Definitions………………………………………………………………………………. 20 4.1.4 Voltage Tolerances ………………………………………………………………………………………………… 21 4.2 Optional Power Connector ………………………………………………………………………………………………….. 21 4.2.1 FanM Signal ………………………………………………………………………………………………………….. 22 4.2.2 FanC Signal ………………………………………………………………………………………………………….. 22 4.2.3 3.3 V Sense Line……………………………………………………………………………………………………. 23 4.2.4 1394 V Pin……………………………………………………………………………………………………………. 23 4.2.5 1394R Pin …………………………………………………………………………………………………………….. 23 5. Other ATX Chassis Considerations…………………………………………………………………..24 5.1 Venting ……………………………………………………………………………………………………………………………. 24 5.2 Power Supply Mounting ……………………………………………………………………………………………………… 24 6. Additional Information ……………………………………………………………………………………..24
原文链接：https://blog.csdn.net/weixin_39585378/article/details/118142514
