I moved my motherboard to a new case have no cards or drives installed yet. I wanted to do a test run to see if all the fans are running. It powers up for 2 seconds then shuts down. If I remove small 4-pin aux power, it will stay running. On the other hand, it will stay running with no memory modules installed it will beep error of course and keep running all fans spin and heat sink fan as well please help
Specs? Re-check the heatsink installation. Generally, a system shutting off after a few seconds is due to the overheating protection kicking in. If a system starts up with just fans spinning, it leans toward a power supply issue, and sometimes improperly set CPU parameters, but that tends to show up more with overclocking.