MSI A520M Motherboard No Power with Processor

[Fernon]

MSI A520M Motherboard No Power with Processor. When remove processor all voltages are genarated ....my processor is compatible this motherboard ...i want to help to repair this

[DynaxSC]

The CPU communicates during POST with the CPU VRM controller to generate all powers correctly. This is part of the bios POST program. For each CPU model the setup of the VRM controller might have different parameters. So bios must know the CPU to setup VRM correctly. Maybe your bios is too old, not supporting your CPU? Another reason could be corrupted bios. Try another CPU, supported by first release of bios. Try upgrade bios with this CPU. If you don't have access to such CPU, backup bios and program newest stock bios with hardware programmer. Take off CPU and depower motherboard to do this. If this will work bios DMI data should be transferred from old bios to new one, check also if motherboard still has a valid MAC address, if not then it also must be transferred from old bios to new one (usually it is on address 1000h in the bios).

If this will not help there must be an hardware issue with the board, most probably with the CPU VRM network, some defect device, or missing smd, cut through track, etc., or your CPU is just defect.

[Fernon@Repair]

@DynaxSC sir i already reprogram bios but same what should i check voltages or signals

[Aliencomputres]

Change CPU.

[Fernon@Repair]

@Aliencomputres same error

[DynaxSC]

Try different memories. Try only one memory, alter slots through all available.

Examine socket/cpu for demages/bent/missing pins.

Short J1 jumper if present on this board (unique feature for majority of MSI boards), this should force the cpu vcore enabling, check then if vcore present. If not, this will mean that something in the cpu vrm network is broken and the vrm controller switches into blocked/safe state. But even if you get vcore this way, board will most probably not POST, as there is some issue present.

Examine board very detailled for missing / ripped off smd devices (resistors, caps), first in neighbourhood of mounting holes, second rest of board. Start with backside. Same for cut tracks. Look for really tiny demages, eg. coming from the top edge of a fallen screwdriver - track cut, demage can be smaller then 1mm, almost invisible to the eyes. Use some x15 magnifier glass. Even an smd resistor can be still present, but broken into two parts and not conducting any more. This is very weak visible, but I have seen such demages already a few times.

If not find any missing devices then measure all supply voltages on the coils, when any is missing then examine if respectivelly vrm controller gets Enable signal. If one has Enable, but no voltage present, vrm might be broken.

Check also all low ohm serial "fuse" resistors (usually 0-2,2 ohms).