To support the AMD 486 DX4-100 and 120 CPUs on the DFI G486-VPA motherboard, these conditions have to be met: 1. G486-VPA Revision A or newer motherboard 2. BIOS dated 9/19/95 (VPA11.bin) or newer for AMD DX4 100 & 120, 3. Common jumpers setting for the AMD DX4 100 and 120 MHz CPUs: JRN1: All On JRN2: All Off JRN3: All Off JP14: 2-3 On JP33: Off JP34: 1-2 On JP35: 1-2 On JP36: 1-2 On JP31: 2-3 On ; 3.45V JP32: 2-3 On JP41: 1-2 On JP42: Off 4a. For AMD DX4 100 CPU: JP18: 2-3 On ; 33MHz bus/external speed JP19: 2-3 On JP21: 1-2 On 4b. For AMD DX4 120 CPU: JP18: 1-2 On ; 40MHz bus/external speed JP19: 1-2 On JP21: 2-3 On Check JP29, JP30, JP11 and JP13 (related to 40MHz bus speed) 5. Please refer to the manual on how to set the other jumpers