PLEASE HELP!!! NOT A NOOB QUESTION

sabre181

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Hello all,

So this morning, I took apart my rig for my semi-annual cleaning ritual (dusting and other general cleaning) and when I put everything back together, my rig wouldn't start.

Here is where I am. I have cleared the CMOS several times, plugged and unplugged all power cables into all components several times, reseated both my graphics card and my processor and heatsink/fan, switched out my DIMMs in all different configurations, all to no avail.

I know everything in my computer is functional, as everything worked last night. When I power on, everything spins up but after maybe 2 seconds of being on, it seems to restart itself over and over again. I have unplugged the reset button cable from my motherboard and then have tried to power on, which leads to the same effect of the computer consistently resetting itself.

I am on my last strings, hoping that someone out on the internet can guide me in my time of need lol. I can give you the specs of the rig, but like I said, i know everything works as of last night, so unless I broke something (which I am fairly positive I didn't) everything is compatible and functional with each other. Thank you ahead of time for any suggestions, i truly appreciate it!!
 
Solution
There are three things that it sound like it may be: 1) Motherboard, 2) Power supply, 3) Weird short.

What I would do is take out the motherboard, and I would look at the caps and the overall board so see if I noticed anything that look discolored/burnt. When I placed the motherboard back into the case I would check that nothing was touching the board accept the screws where they should and the rear plate where it should. This will reduce the likely hood of a strange short and if you can visually see a bad spot on the board you know it’s the board.

Then I would move onto the power supply. Personally I have a few power supplies sitting around so I would put one in and see if it posts; maybe even a second one if the first doesn’t boot...
Start by unplugging all the optical and hardrives. If it posts and doesn't reset itself, then check the bios settings. If you were overclocking or using special settings, perhaps your windows operating system needs to be repaired or reinstalled. Set the boot order, ram voltage or timings if needed, sleep mode (if used) save and exit. Then start connecting your drives one by one until you get the problem again. That's about all I can suggest.
 

Pro Llama

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When you took out your cpu did you clean the heat sink and cpu then reapply thermal compound? If not the cpu could be over heating making it crash.

When you boot does anything display to the screen? If so can you get into the bios settings?
 

C00lIT

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try making it post with the strict minimum...

so

CPU
1 bar of ram
1 videocard (unplug and replug it) or remove it if you have an onboard video.
no harddrives
no cdroms.
Remove any other components... when it doesn't run, try running with the strict minimum.

And make sure the "PCSpeaker" is plugged in properly... as when a pc fails to post it should beep an error code that can identify the problem.

if it doesn't boot, try a different stick of ram in another slot.

Confirm that the 24pin power is properly connected (I am sure it is)
confirm that the 4pin "Pentium4" connector is plugged into the motherboard.
confirm that the power is connected in your videocard if it requires one.

If it still gives you trouble... Go watch a movie for an hour and a half, take some air... I am serious as when you come back you will be far better at troubleshooting... worst case scenario, undo the entire computer and rebuild from scratch... that usually works for me.

It is always helpful to have spare parts at least for testing.
 

sabre181

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I did a clean application of AS5 to both my northbridge cooler and my proc hs/fan. When i start up, nothing is displayed on my monitor... it just cycles between analog and digital until it times out and displays "check cable connection".
 

sabre181

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\

I did what you suggested, unplugged the hdds and optical drive, switched out the ram, checked the power connectors, kept everything to a minimum, and it still does the same thing. There isnt even a beep from the mobo for posting. I did notice that the network led, the little green light that flashes when an ethernet cable is plugged in, pulsates every second, i mean it says solid for a second, goes out, then stays solid again, almost like the computer is constantly being restarted or something. I'm going to chill like you recommended for a bit, hopefully to come back with a clear head. I essentially already rebuilt the computer from the ground up this morning, and thats the reason why I'm where I am now lol. Thanks everyone for teh suggestions so far!!
 
sounds to me that there is a wire shorting out somewhere i know u said u disconected the reset but did u try disconnecting the whole front panel and just short power pins on the mobo. How i do it is use a small pair of tweezers to short the switch. If it still does it i would suggest maybe trying a new power supply weird stuff happens to electronics man wil be working one day next day it wont and there will be no reason for it.
 

Pro Llama

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There are three things that it sound like it may be: 1) Motherboard, 2) Power supply, 3) Weird short.

What I would do is take out the motherboard, and I would look at the caps and the overall board so see if I noticed anything that look discolored/burnt. When I placed the motherboard back into the case I would check that nothing was touching the board accept the screws where they should and the rear plate where it should. This will reduce the likely hood of a strange short and if you can visually see a bad spot on the board you know it’s the board.

Then I would move onto the power supply. Personally I have a few power supplies sitting around so I would put one in and see if it posts; maybe even a second one if the first doesn’t boot. If you have the same advantage, drop in the other power supply. You can also use a power supply tester but most people don’t have one. I wouldn’t suggest putting your power supply into someone else’s pc because if the power supply has a short it could burn up the other pc’s motherboard.
 
Solution

sabre181

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Disconnected the front panel stuff and still nothing. replaced power supply and still nothing. I am beginning to think i f'ed up my mobo somehow... maybe when i reseated my northbridge hs/fan? suggestions? There was a somewhat loose cap, though it was only slightly bent. Other than that, I can't see any other physical problem.
 

Pro Llama

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Did you bend the cap while cleaning the pc and did you try to bend it back? Also how is the cap loose, do the pins stay still in the motherboard and the body of the cap moves or do the pins move with the body?
 

Pro Llama

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Pretty much if you bent it and didn’t bend it back it could be touching something which could cause a short. Bending it back may fix the problem so I would try that first. Either way bending it could have broke the solder on the motherboard (not that likely), or broke the actual cap. If the solder is broken you can try to solder it back but it would be very hard to do and in all likelihood you would end up with a bad connection unless you have done a lot of soldering. It would be worth a shot considering you will need a new board anyway.
 

sabre181

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The cap was bent after i cleaned everything, most likely after i put everything back. It did bend back without any resistance, however, I did notice that it isnt touching the motherboard like all of the caps are around it. The pins were and still are connected into the motherboard.
 

sabre181

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Just ordered a new mobo, i had the ga ma770t-ud3p and am getting a msi 770 c45. I'll post something when I get the board this weekend or so, hopefully with good news. If anyone else has any other suggestions in the mean time, keep them coming! Thanks again to everyone who helped, this is why I love Toms Hardware!!
 

fusiondataservices

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The loose cap should not have messed it up as long as it is not broken off. I think you should take out the good old multimeter, or a psu tester, and try that first. Most of the time when I see this, this is the issue. It may not be, but I really would not rule it out.
 

sabre181

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I dont have either a multimeter or a psu tester. I did switch out psus with a functional one that has the right wattage and amperage and still had the same result.
 

sabre181

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The last thing I did before I ordered a new mobo was running just the psu, mobo, gfx card, proc, and ram outside of the case, and the thing still didn't power on.
 

jedimasterben

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Sounds like what happened to a computer at work yesterday. I went to start it up and it did absolutely nothing. Replaced the power supply, booted with nothing but the CPU connected, and still not even a beep.

MBE (parent company of the UPS Stores) said it was definitely the motherboard, and that we would either a)have to find a new motherboard (the thing runs an old 478 P4 with an AGP slot, on an obscure looking HP rp5000 mobo, so most likely no luck), or b) buy the new model from the rp line from them, which came to around $1700 after taxes (OUCH!). I just checked the specs on the rp5700, and it at least comes with a Pentium Dual Core and 1GB of RAM. Oh well, what can you do when the software locks you out of building your own computers?
 

branflakes71

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It does sound like the motherboard in this case. Good luck with the new one.

Unless you're in a really dusty room, you don't need to do all that work to clean out the computer. Just shut it down, disconnect it from the power outlet, and use the compressed air to blow out the dust. May save you some headaches/money in the future.