Computer Won't POST Anymore! HELP!

**tgxiii** · March 30th, 2004, 12:03 AM

Abit IS7
P4C 2.4GHz
Powercolor Radeon 9700 Pro
Corsair XMS PC3200

Those are all the essentials. I was using it this afternoon when it suddenly turned off all on its own. I thought it may have been due to the hot weather recently, so I let it stay off for a few minutes then turned it back on. When I did, all fans started to spin, I heard the hard drives powering up, and the lights on the CD drives turned on. All that but no POST.

I already took all the unessentials out so I only have a CPU, video card, and memory in the mobo. I even replaced all of those with known working one: a P4 1.6GHz, Corsair Value Select PC2100, and an ASUS TNT2. I've reset the CMOS numerous times.

Anyone have any ideas? TIA

Edit: Here's an update. I transferred the P4C 2.4GHz and Corsair XMS PC3200 into an old mobo, an Intel D845GRG. Both worked fine in it. I still have yet to check the video card.

**John Prophet** · March 30th, 2004, 12:30 AM

power supply?

**tgxiii** · March 30th, 2004, 01:00 AM

I'll try that. To be honest I didn't think about that. I assumed it was okay because the green light on my mobo indicating that it's getting power was on and all the case fans, hard drives, and CD drivers would turn on.

**mar122999** · March 30th, 2004, 01:23 AM

You could try is to completely unplug the system and leave it unplugged for 10 minutes. Plug it back it and try it. Seems to work numerous times with troubleshooting boot problems.

**mar122999** · March 30th, 2004, 01:24 AM

But I'm guessing you already did that since you switched parts.

**tgxiii** · March 30th, 2004, 01:33 AM

Yup, tried that, mar. I'm starting to think it's my motherboard. I tried to turn it on just a few minutes ago and nothing would spin up anymore. So I switched to a known working PSU and I get the same result. Anyone have any other ideas?

**mar122999** · March 30th, 2004, 01:39 AM

Well, I would like to know what caused it to go out all of a sudden if it was the mobo. You may want to physically look at the mobo and see if you can find some leaky capasitors, wet or burnt chipsets, or burnt marks anywhere else on the mobo.

**tgxiii** · March 30th, 2004, 01:43 AM

I looked over the mobo. All the capacitors were still flat; none were bulging. As far as I can tell, the Southbridge is fine. I didn't see the Northbridge, though, 'cause the NB fan is in the way. I'll check that out later. As for burnt marks anywhere else, I could not find any. To be honest, I don't know where to look. I checked the MOSFETS, the CMOS batter, and the Southbridge, but that's it.

**tgxiii** · March 31st, 2004, 07:47 PM

bump

C'mon, guys. I don't wanna take this to a PC repair shop.

**AzKidd69** · March 31st, 2004, 08:58 PM

you try swapping out PSUs? what about video?

what about a CMOS reset just for giggles?

**Messiah89** · March 31st, 2004, 09:03 PM

Originally posted by AzKidd69
you try swapping out PSUs? what about video?

what about a CMOS reset just for giggles?

He said he resetted the CMOS numerous times.

I'm thinking it has to be the motherboard.

**tgxiii** · March 31st, 2004, 09:35 PM

Okay, update:

I got a new board, another IS7. I put all my old hardware into it, it POSTed. I thought, great, so I proceeded to the BIOS. As soon as BIOS screen came up, I lost video. The fans were still spinning, though.

I took everything out again. Put in known working CPU, memory, and video card. Pressed the power button, I get no POST but all the fans would spin up.

So I replace the power supply. I got a beep! I then put all my old hardware back in, and now I'm browsing TechIMO with it!

I went back to my old IS7. I plugged a known working power supply into it, along with a couple of fans, but the same thing happens. Green LED light is on, but the fans won't spin up. Could it be that my old PSU failed and took my mobo out with it?

**AzKidd69** · March 31st, 2004, 09:45 PM

you try taking the mobo out of the case and putting it on a piece of cardboard/wood/something_else_non-conductive and see if it posts not in the case. if so the mobo is somehow grounding out to the case
Also..... haven't looked into the specifics of this board yet. is it possible that a vital jumper fell off?

Messiah89> missed the part about him resetting the BIOS

**tgxiii** · April 1st, 2004, 12:21 AM

Yup, tried that. The old mobo still doesn't work. This new one is working now, however. I checked the old mobo over and over again. All jumpers are in place. I tested it on a cardboard box outside of the case. Still no go.

**roley** · April 1st, 2004, 02:06 AM

If you have tested different things...and then you try a different PSU which gets things working again....then it tends to suggest PSU was bad.

But, as with Azkidd69's post...just remember to keep as much of the system same state (ie ceteris Paribus) all other things equal if I do this, does that fix it....one at a time...it is the only way to be sure.

That is the rule in troubleshooting.

Rohan