Remark: when testing motherboard display, most repairers only test the CPU socket and PCI data cable, address cable. However, such testing only covers few cables of BGA. Therefore, it is difficult to repair it successfully. It is recommended to use multimeter or AGP slot tester to test every slot of motherboard such as DIMM, AGP, PCI-E, and IDE etc. When the open circuit or short circuit point can be tested, error can be confirmed.Once The Motherboard is Off you Need To Press The On button of The Tester if All The Lights Light Up The AGP Card is OK .You Can Then Leave The On Button in off state and then switch on the board only the top right lights will run .

Please Do Not Press The On Button Once the Motherboard in In ON state .