Autostart circuit helps ATX motherboards resume operation after power interruptions

摘要

UNLIKE LEGACY PC motherboards, an ATX-style motherboard controls its power supply's on/off state. If ac power fails, many ATX motherboards do not automatically restart when power returns, and that behavior is unacceptable for a server system that must provide near-continuous service. Although some PCs provide BIOS configuration selections for "wake-on-LAN" or "wake-on-modem" operation, these options depend on another computer to provide the wake-up call. A few ATX motherboard chip sets offer an "always-on" BIOS option, but chances are, the motherboard that's available for your server system isn't one of these.