Strange failure - suggestions???

[Ed_S]

Last night, while online, I had a lockup. No response to mouse or keyboard. No biggee, right? Just reboot the beast.
Only... it never came back.
Power up seemed fine - fans & drives spin up, all drive lights come on & appear to be in normal sequence, but no video.

OK, vid prob, right? Tried another AGP card, then a PCI one - nothing. Tried original card in another machine, works fine.

Power? Tried another PS. No go.

Stripped it down to basics - ram, vid, cpu. Nothing else.
No go - still no POST, no beep codes, nothing.

Swapped CPU. Swapped ram. Nothing. RAM tested good in another machine - can't test the CPU, don't have another board capable, but pulled a lesser celeron from another machine & put it in this one w/o result, cpu still good when reinstalled to it's machine.

Only thing I can think of that I didn't do was to try the original ps in another machine - very impractical in this case. Custom made dual ps case - this ps runs only the mb, floppy & zip drives, the other one carries the big load.

My conclusion - most likely the mainboard's bad.

But why? No recent changes to machine in two months. No power issues in house. No warning signs. No unusual stress on system. Heck, it's even had the case panels installed for quite a while, unusual for me!

I've never had a board fail under these circumstances, and I'm not one to replace something w/o knowing the cause of failure.

Unless... did I miss some other possibility?

Board - Soyo SY6BA+!V

[twiztidtruckie]

my guess is the mobo went kaputz....seems like you tried every solution i coulda came to and still no go...any physical damge that you can see?..like burn marks etc...

Truckie, Juggalo King!!!

ps: what was the tempreture readings last you checked?...mybe cpu fan died and cpu cooked....or possibly you may have over looked plugging in your monitor?...lol..sounds dumb but ive done it...

[Ed_S]

No burns, no swollen capacitors, nothing loose. CPU fan's fine. No clue as to temp - I've never really monitored it.

Monitor's fine on another machine, but I also tried a different one just for grins...



BTW, thanks for trying - & no suggestion's too "dumb" - I'm actually hoping I missed something obvious...
Tearing down & reconfiguring this beast for a new board is NOT something I want to do!

[Bovon]

Originally posted by Ed_S
Stripped it down to basics - ram, vid, cpu. Nothing else.
No go - still no POST, no beep codes, nothing.

I gotta ask!! even tho you have said only ram, vid cpu and nothing else...was the keyboard attached?

My Daughter had a failure a month or so ago, and it turned out to be a bad cable near the end where it plugs into the motherbaord..the failure acted very much like you have described.

[John Prophet]

Also maybe try to reset the bios.

As far as it dying. hehe, thats the way it goes...not EVERYTHING dies at boot up...sometimes a part just lets go unannounced. Same for cars, light bulbs, electric fans, etc.

JP

[Ed_S]

Well, thanks for the suggestions!

Bovon - got my hopes up there! You're right, I hadn't unplugged the KB or mouse. Went & tried - no change. Also unplugged the front panel connectors except the power switch (which IS working). Again, no change.

Dug out an ISA vid card & tried that - with it, I get a momentary screen flicker on power up, that's more than I get from AGP or PCI cards.

JP - haven't tried a bios reset yet, but will as soon as I look up which jumper it is. It's not clearly marked on board...


If it's dead, so be it. I'd just like to know what happened to avoid a re-occurence.
Also need a source for another - with this application, my board choices are extremely limited.... it needs to have 4 ide ports to run 8 devices, and I'd like to replace as few components as possible. Ideally, another SY-6BA+IV is what's needed.

[nunyadam]

have you tried a different hard drive. you mentioned trying all else. clearing the bios wouldn't hurt.

[nunyadam]

have you tried a different monitor?

[MRCOMPUTER]

Ed. Take another look at the caps. I have 2 of the same board I repaired. The bad caps did not appear swollen. Slight stain at base and more evident after removal for replacement...

[Ed_S]

Mr C - Can't see anything even with a magnifying glass - but it IS still in the case. I'd be willing to bet you're right, though - under the glass, two caps appear domed at the top, as though swollen, while others of the same exact size & style are flat.

Two big questions for you, ol' buddy ;D

You've GOT one?? Willing to part with it?

You can replace caps on a board?

PM to follow...