Motherboard Problem

[Ripley]

I'm beginning to think this MB is bad. To test the switches I checked them with my multi-meter, and to be sure I used another set of switches, same problem. You hit the switch and nothing happens, just like the unit is unplugged. No fans twitch, nothing. After the tear down and re assemble ( I found two stand offs that were the "through the board" type and replaced them with flush mounts) The computer started fine. I shut it down and restarted it with the on button a half dozen times. I then dug into the network issue with no resolution other than to buy a ethernet card and try using that instead (should have it today or tomorrow).

I have this power supply.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139031

It is only 7 months old and when the computer is running the voltages look good in the monitoring software.

As of this morning, the computer will again not start with the on button, completely dead. 

If the software you are using to watch voltages is running real-time, Voltages shouldnt fluctuate much at all. If you are seeing voltage fluctuations of .5v or more there's a problem there. If the ground in the power supply (or one of the grounding screws in the case) is causing an issue you could see the random boot issues you are having as well.

From a real-life-experience standpoint, years ago I had an old emachine computer that would only boot when it wanted to boot. Sometimes you press the power button it would boot fine, sometimes it wouldnt do anything at all. A few months later it stopped working altogether. What was it? Power supply.

Bizman, from what I gather, sounds rather experienced in this field as he's already stated a few things that I didn't know myself (like using a wire or paper clip to make a fan on the power supply spin, thanks for that) so I would take his info to heart as well. But if you ask me, I still think your power supply is the issue here. From what gather I can say its a power issue with confidence, but the question is whether it is with the cabling, the power supply, the motherboard, Or MAYBE a grounding issue with the case. You said that you have the new motherboard in your case now, right? The chances of two separate motherboards having problems back-to-back are relatively slim.

What about cabling? Are you plugged right into the wall? a UPS? power strip? extension cable? While these things very rarely cause any problems, I did hear of one case where the power strip one user was using was very old and not putting out the required power for his computer to function properly. As I'm no expert at the electrical side of things, I only offer that as a suggestion because I have heard of it happening.

[The Fugitive]

OK, heres how it stands at the moment...... I know ya'll can't wait to hear 

I borrowed a PSU from my son. I put it all together and the computer booted up. I ran the installer/driver program for the on-board network card and low and behold, it installed the driver turned on and I can now log on to the internet. It's early in the testing. but It did boot and load, so we are ahead of where I was this morning.

I'll keep at it and let you know how it goes.

Thanks again for all the suggestions. 

[The Fugitive]

OK, I ran some stress tests on it last night. I shut it down, let it sit, and rebooted a number of times. The voltages are steady with an occasional 2/100 of a volt fluctuation on the +5 volt line when I work it. It pretty much took everything I can think of to throw at it. I shut it down last night and it fired up this morning with ease. So I maybe <knocks on wood> out of the woods.

So I'm thinking the issues I had with the old MB may have strained the PSU. When I added the new MB the PSU decided then was the time to finally quit. Would it be so tough for a PSU company to add a number of LED's on the final output of the PSU to show when there was power there. Could they also add one more LED and have it tie into a +5 spot on the MB? This way trouble shooting would be so much quicker and easier.

On our video game systems everything was much easier to get to. Main control boards had voltage test points on them, PSU had open connector areas were you could easily test them. Same with the pinball machines as well. Oh well, I miss the good old days.

Well after I clean the snow out of the driveway I guess I'll get the RMA going for the bad PSU, and do some flying to see how it holds up.

Thanks again for all the tips and help. <S>

[Bizman]

Your guesses about which component broke the other are as good as mine. A shortcut inside the motherboard's circuitry board may have caused the PSU to fail, or the PSU may have produced so much ripple (which can't be seen with a multimeter, you'd need an oscilloscope) that it caused the mobo to fail. Or both have been monday builds.

[The Fugitive]

SO here's the latest fun..... After I swapped out the PSU with a used one the computer loaded fine, ran fine, I even flew for a few hours with it. I RMAed the old PSU and figured I'm out of the woods.

This morning I go to boot the computer and it stops in it's POST.... or seems to. The memory passes, the CPU passes, and the video passes (all according to the LEDs on the MB) when it hits the "boot device" it stops.... or seems to. I double and triple check everything, even throw in a different HD to see if thats it, nothing. So I boot it again, it has the ASUS screen with the "Hit F2 or Delete to enter the setup mode on the screen and is stopped on the boot device LED again. I leave it there and start hunting for answers on my wifes computer at the other desk. 15 minutes later out of the corner of my eye I catch the screen go to the "Windows did not start properly...." screen. I tried to get it to go into the test modes and resets, but it seemed to lock up.

I cleared the CMOS, checked everything again and booted it again. Again it seemed to lock up, but I waited. 15 minutes later it went to the windows didn't load...." screen again, so this time I switched it to load windows normally and eventually it loaded. Total boot time from pushing the button to everything loaded and working .... 55 minutes!!!

The kicker is the thing runs like it doesn't have any problems. I'm thinking running it for those few days on the original (bad PSU) may have damaged the MB. Anyone else ever seen this, or know anything about a 55 minute boot cycle?

[Skuzzy]

A power supply, going bad, can damage every electronic device in a computer.  The damage may be subtle, depending on the component.

[Bizman]

A while back, when Windows encountered a problem, it would slow the HDD down one notch. Until lately it was easy to check in the Device Manager, Primary IDE Channel, Advanced Settings. If the Transfer mode was PIO instead of DMA , or the current transfer mode was below Ultra-DMA 5 or 6 for the hard disk, that would be the culprit of a slow machine. The easy fix was to remove the Primary IDE channel, reboot and let Windows reinstall it with correct values. The same can of course be done with SATA devices. If that doesn't do the trick, I'd backup everything valuable and then run a hdd diagnose test.