s5-1200z Desktop fails to power on.

[NMBOpen]

Computer fails to power on. Disconnected power cord, power supply light goes out after several seconds. Reconnect power cord. Push power button. CPU fan does about two revolutions and stops. Peripheral fan barely moves. Holding power button for 10+ seconds while disconnected had no apparent effect.

[Grzwacz]

Greetings,

Welcome to the forum.

I am not a HP employee.

This symptom could be the power switch, power supply, or the motherboard. And possibly a component connected to the motherboard or a bad peripheral device.

You have to troubleshoot each component.

Edit, I start by cleaning the internals using compressed air or a Dust Buster. Check all connections (internal and peripherals)

I usually proceed by disconnecting all internal SATA , USB, and discrete graphics devices one at a time (use onboard graphics). Only connect a monitor. Try to POST after disconnecting each component.

Remove all RAM. Try to POST. You should get a BIOS error if the motherboard is responsive.

Try a different power supply.

Finally the power switch could be the problem. You can short the motherboard power switch pins to attempt a POST. You have to know what you are doing.

A good, local, PC tech should be able to find the cause.

Regards

[NMBOpen]

Geek Squad tested power supply OK, sent off to Best Buy Service Center near Louisville, KY. Said the motherboard was bad but couldn't get another. S/N 2MD2210YR6  Returned unrepaired!

[Grzwacz · Accepted solution]

Hi,

Sorry to here this.

You could try eBay for a reconditioned MB using the part number. 

Regards

[NMBOpen]

Ordered from eBay. Should be less painful than replacing entire computer and trying to transfer/recover data and settings from the hard drive. We'll see.

[NMBOpen]

Found local tech to install motherboard. His first act was to plug in a different power supply. Lo and behold, that powered up immediately. Ordered one to fit the Slimline case. May return the motherboard if shipping doesn't eat the refund.

[NMBOpen]

Resolved with power supply replacement. Motherboard diagnosis by Geek Squad was incorrect.

[Grzwacz]

Hi NMBOpen,

I thought you probably had a power switch, power supply, or motherboard problem.

A good local PC tech usually does a better job when diagnosing the cause of the problem.

A new power supply is less costly compared to a new motherboard and a new operating system, plus other components unless you buy the same motherboard.

Regards