System not booting

[Arlos]

OK, got a couple ideas of what's going on here, but wanted to get some other people's thoughts.

This is my main PC. Was working fine up til yesterday morning, indeed, it had been on for several days straight, with no heat issues, no complaints, etc. Turned it off yesterday when I left for work, came back, and now the thing won't boot up at all.

I click the power button, and everything sounds normal; I can hear the fans start, the drives tart spinning up, etc. Then it does 1 beep, which sounds like the beep it would always do right before starting writing to the monitor and giving me my option to go to the BIOS, etc. However, now, right after that beep, power cuts out and everything goes dead.

There was a moderate amount of dust in the case, but I've gotten most of that out at this point, I think. Tried popping out and re-seating the video card, as it craps out as it is about to start using it, but same problem persists.

I am guessing I have a short in my power supply somewhere, but it's weird that it would start up just fine, and not die til it was about to start outputting items to the screen. Doubly odd given that it was working perfectly before I turned it off, now won't come up again.

I doubt it's anything virus-related, I run AVG antivirus + anti-spyware memory-resident and keep it up to date always, and I regularly scan the system with both AdAware and SpyBot. So, I am guess it has to be a hardware issue of some kind, but was hoping someone out there knew exactly from the symptoms.

Thanks much.

-Arlos

[Lueyen]

I had something very similar a year ago. I first tried replacing the mother board only to find out it was indeed the power supply... of course it was a good excuse for a motherboard upgrade~.

You might try disconnecting everything power wise besides the mother board, with drives disconnected if the power supply is going out and just getting overloaded doing this might get you a screen (as there will be less drain on the supply).

If you have a good machine you can set them side by side and hook up the power supply from the good one to the one that won't boot (save you the headache of doing a physical swap.

Remember you only need the main power to the motherboard to get the initial boot up screens as vid card, memory and processor are all powered from that single cable. Without hard drives powered it obviously won't boot, but you should still get a screen to confirm that it's a power issue.

[Arlos]

Not a bad idea. I don't have a 2nd desktop machine, so I can't try the power supply swap idea, but I'll give a try later today disconnecting the power supply cables to the drives and see what happens.

Still, I'm not sure it's insufficient power, since I hear everything start up. It honestly acts like I'm tripping a circuit breaker of some kind somehow; like something is generating feedback or power is spiking from something, and the power supply is cutting out rather than blow.

Still, definitely a worthwhile suggestion to try, I'll give it a spin later today when I get the chance and see what happens.

Anyone else have any ideas?

-Arlos

[dammuzis]

sounds like power supply to me. buy a cheap one a frys and do the post and see what happens

[Reynaldo]

I had a similar problem and it turned out being my DVI port on my video card had died (2 months after warranty expired, woohoo!). It had a VGA out on the card as well, so I swapped out cables and it worked fine on the same card.

[The Kizzy]

I had the same problem before and my flat screen would pop on for a split second and then it wouldn't work, had to use an old boxy monitor. What had happened was when I was moving my computer into the other room, I crossed some power cables and I didnt have enough voltage or something. Anyway......in hopes of not sounding like I know what I am talking about (I kknow what I am trying to say Try checking yor cables and make sure they are all plugged in correctly. It may be something as simple as that.

[kaharthemad]

arlos this is gonna sound like a wierd idea but...
pull the cord from the wall and let the box sit for 1 hour.
then plug it back in and see. I know with some brownouts or surges the capacitors can get overcharged. only way to fix it is to let the caps discharge on their own. if there is current supplied to it they wont discharge.

[Lueyen]

I had a similar problem and it turned out being my DVI port on my video card had died (2 months after warranty expired, woohoo!). It had a VGA out on the card as well, so I swapped out cables and it worked fine on the same card.

Was it shutting the machine off though? I can see not getting anything on th video but I would think the machine wouldn't power down. Also usually if there is a problem with the video card you will get more then one beep (the number would vary depending on the bios error coding).

arlos this is gonna sound like a wierd idea but...
pull the cord from the wall and let the box sit for 1 hour.
then plug it back in and see. I know with some brownouts or surges the capacitors can get overcharged. only way to fix it is to let the caps discharge on their own. if there is current supplied to it they wont discharge.

Good idea Kahar, that's a possibility, for a truly shocking experience you can manually discharge them 8D.

[Naethyn]

If the machine powered down off after the beep it is a power issue.

If the machine sat with a black screen after 1 beep it is a memory issue.

[Arlos]

Yeah, it powers down after the beep. I know about the beep error code sequences if the video is dead, or something else major is wrong, indeed, at one point I had the codes memorized. However, that's not what I'm getting, it's just doing the normal beep then boom, power gone. I can click the power button again right away and it will start the whole process once more. I've had it unplugged for the last 24 hours or so, when I get home I'll try hooking it up again and see what happens. My video card has 2 DVI output ports, though I have a CRT monitor and a amusing a DVI-VGA conveter, and I'll try moving it to the other port on the video card, just in case.

After that, I'll try the idea of only providing power to the motherboard and video card and see what happens.

-Arlos

[ClakarEQ]

Last time I had a problem like this it ended up being the bios. There was a fan cooling the bios chip and I didn't realize it had gone bad, everything was fine until I powered down, then on again (not). It would boot upto about 2mins and then shut off.

MoBo fixt it tho.

[Reynaldo]

oh woops, my reading sucks =(. I was under the impression that the computer was staying on after the beep, just no picture/boot up.

[Lueyen]

How did things come out Arlos?

[Arlos]

Still no luck yet, though I haven't had any free time to do much, as I have needed to deal with my car becoming problematic as well as work being really busy. Gonna be getting together with a friend who has a voltmeter over the weekend to look at it directly. Also, did make a quick trip to the computer store and picked up an Antec Truepower Trio 650W power supply just in case. I figure if it's not the power supply, I can return the new one easy, and if it IS, I've already got the replacement on hand.

-Arlos

[Arlos]

Yep, it was the power supply. Put the new one in, hooked everything up, and boom, running fine now. Just glad it didn't take anything else out with it when it went.

-Arlos

[Lueyen]

Yea no kidding, a friend of mine had a power supply go bad once and it soldered the lead to the motherboard... new board and new supply ><.

[Martrae]

Yeah, mine died in Feb and took my hard drive and cd-rom with it.