Motherboard boot problem

[Garling]

I am upgrading a clients computer with a PC Chips MB-825G motherboard and an AMD Sempron 2400+ CPU,512 PC 2700 power supply is 250 Watt. I can't get the board to boot. I have replaced the MB, CPU, and memory, still no boot. I get power but no signal to video. I am at a lost, could the power supply, 250W be giving me this problem. It is the last thing that needs to be replaced, it works fine with his old MB, AMD 900 MHz, 256MB PC - 100.

Thank you

 

[edfair]

PCCHIPS motherboards ship with the CMOS clear jumper installed. Try switching it off and see if that helps.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[Garling]

Done this aready, same prob.

 

[edfair]

Yes, it is possible that the PS is the culprit. You would really need a meter to see what is coming up.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[paparazi]

Boot or Post?

Are you trying to boot from an existing install of Windows? if so this will often result in a non boot due to the fact the OS was configured on another platform (reinstall required)

No post?

usual:

One or more mounting posts in in the wrong position so shorting the motherboard to ground.

The heatsink/fan has been fitted 180degrees out, overheated and damaged the CPU (recess in the base of the heatsink must be positioned so it is mounted over the raised cam box of the CPU socket)

The power plug or other connection is not properly pushed home (remove and refit all power connections)

Clear cmos

A plugged in device is preventing post/Boot (unplug all addon cards, IDE cables, molex connectors etc) typically if a power supply has gone bad often it burns out a controller chip on the hard drive putting it to ground, this prevents post) this can also happen with a CDrom device as well.

Bad PSU

Martin



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[Garling]

It will not POST

Will not POTS prior to mounting to MB

Fan is mounted correct

All plugs have been checked

CMOS have been cleared and recleared

All devices have been removed, MB has on-board video, also tried other video cards.

Would it be a bad PSU even if it works with prior MB and CPU. Or would the wattage be causing the probs.

 

[edfair]

It could be pulling enough current that the P/S is crowbaring off. But you should see some action on the fan, maybe 1/4 of a turn, indicating that 12v was coming up. Or on the P/S fan.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[Garling]

I am seeing the fan on and turning and other devices come on ie..CD-ROM, HD etc, when they are connected.

 

[wolluf]

I'd certainly try another PSU.