motherboard or CPU?

[crokett]

Dad's machine got hit by lightening over the weekend. It is an Intel 650mghz on an ATX Tyan S1864 mobo. When you turn it on, nothing happens. When you plug the power supply in, it starts to spin up (normal) then shuts off (also normal). I stripped the machine down so all that is connected is the power switch and the CPU, same symptoms. Looks like it is the motherboard and/or processor. I've been out of tech support 2 yrs now, so just wondering if I missed anything else.

Guess this is a good excuse as any to upgrade.

thanks

[xhadow]

have you tried to change the power supply?
It could be a power supply problem, If you dont see anything burnt or damage on the motherboard or cpu

[Icarus]

Hopefully there was a surge protector of some kind attached...that would stop 'most' of the damage. Usually the Power Supply is the first to fry, then the board then everything else...

I would think the CPU would go with the memory, PCI cards and video...

[dunbar]

If the surge was able to get into the modem (You think: maybe try the modem in another PC? Beware - this may not be a good idea), then the most likely damage was the mobo, as the modem would connect to the PCI slot. ISA/CNR slot, USB port or (gasp) serial port makes no difference: the internal connection is the mobo for all of them. If the surge arrived through a NIC or audio cabling or anything connecting into the expansion cards on the PC, same idea, the mobo is likely fried.

But!

If the surge arrived via the power line only (not totally unlikely, but weakly possible), then possibly a new power supply will fix you right up.

Maybe try the mobo on a different (properly rated) power supply, but again, things may go poof on that different power supply, so eye protection and fire extinguishing is in order.

Or

Toss and redo from start.

And

Unplug everything from the PC next time.

Lightning cares little about the flimsy surge protection devices which most people buy... if lightning can jump miles from cloud to earth, the little surge suppressor device is only so much dandruff to a close strike. Add in the false sense of security developed because the dead devices never announce that they have "left the building" - the surge suppression elements might have died days ago, you'd never know.

[crokett]

Originally posted by xhadow
have you tried to change the power supply?
It could be a power supply problem, If you dont see anything burnt or damage on the motherboard or cpu

Power supply seems fine. I've built 8 machines with the ATX connectors and serviced dozens more. If I plug the machine in, the power supply spins up like it is supposed to. Al the other dead ATX power supplies I've seen don't spin up when you plug them in. Of course, there is a first time for everything. I suppose I could borrow the power from my server, though it is a pain to switch it out.

[Timothy L. Miller]

Originally posted by crokett


Power supply seems fine. I've built 8 machines with the ATX connectors and serviced dozens more. If I plug the machine in, the power supply spins up like it is supposed to. Al the other dead ATX power supplies I've seen don't spin up when you plug them in. Of course, there is a first time for everything. I suppose I could borrow the power from my server, though it is a pain to switch it out.

Personal experience: I had a power supply that worked perfectly as far as starting up. But it was fried, and from delivering an improper supply, fried 3 mobos before I managed to realize that I wasn't just having really bad luck with motherboards.

[banzaikai]

Howdy.

Timothy's right! Remember, the power supply sends all kinds of voltages out to the mobo. The +12V to the fan may be fine (causing it to spin when plugged in), but all the +5V and +3.3V could be completely shot.

A good tip for all those PS swappers: When testing the new supply, always plug in at least one of the hard/floppy/cdrom drives. Why? Most ATX supplies require a LOAD to be present for the switching circuitry to work. If there is no load (say, the mobo has some open rails or blown fuses), then the power supply may very well go into saturation, and self-destruct (yes, I've had it happen to me while demonstrating to another tech how to turn on the ATX with a small screwdriver. I didn't even have time to find the pins to short when the PS sparked into oblivion...).

Hope this helps...

banzai

[banzaikai]

Hey!

I just got promoted to "Junior Grasshopper"!

Rippa-na!

banzai

[crokett]

Thanks. I have a friend who has a spare PS. I will check it out.

[MadeInChina]

Originally posted by banzaikai
Hey!

I just got promoted to "Junior Grasshopper"!

Rippa-na!

banzai

When do I get to type in my own choice of what "type" of forumuser I am? :rolleyes:

[mdwatts]

Originally posted by MadeInChina


When do I get to type in my own choice of what "type" of forumuser I am? :rolleyes:

Can you not change it in your profile?

Would you like a suggestion? :D