# ArghhhHH!!!! No power to motherboard!!!!



## Yakkum (Dec 17, 2000)

Okay, so I had a previous problem with my Asus motherboard (a7n8x-x) and narrowed it down to bad ram, or at least that's what I thought. Anyway, I just got my new stick of ram today, pop it in the system, try to power up and NOTHING!

I re-open the case and check to see if anything is amiss and there's no light on the motherboard. NO POWER GOING TO IT AT ALL, or so it seems. 

I hadn't touched the computer since I had removed the ram from the other time. 

Did I fry the mobo somehow even though power and it wasn't plugged in? 
How easy is it to fry the motherboard?
What else could be causing the problem besides a bad powersupply?

What can I do? (I have already tried resetting the CMOS with taking the battery out and switching the jumper and whatnot)


And if motherboard were "fried," "toast," "dead," Would there be any chance of the little LED still lighting up? 
Should I be concerned with PS or MB? I'm thinking MB, but I suppose the power supply could have just failed or something too by chance. I dunno.


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## tribe (Feb 10, 2004)

I know exactly what your going through. Recently my computer has been working fine then out of nowhere it starts acting weird. First with bugs and random crashes, then random restarts, BSOD and now it wont turn on. All that happens is the fans start up for about 1 second and then it dies. The light on the mobo still remains on though.....well anyways I'm taking it to my cousins to see if its the mobo, ram, or processor since I already RMA'd my power supply thinking it was the problem. 

Ill let you know the good news. My suggestion is that it can either be the processor or psu in your case since mobos are not known for dieing out (unless theres some kind of shortage, crack, or explosion  ).


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## MustBNuts (Aug 21, 2003)

Could you have loosened or accidentally disconnected the wiring between the on/off button and the mobo?

MBN


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## bowmar (May 30, 2003)

Hard to say Yakkum, but the board can be 'fried' and still light up led's, the CPu fan can spin up Etc.
Swopping out PSU is the way to go, then memory and processor, until you get the culprit, extremely easy i'm afraid to fry a board.

Tribe, on your problem, when i've seen this before its either been a faulty CPU or the mobo has been shorting somewhere, usually an extra stud in the fitting or a _renegade_ screw Etc rolling under the mobo and causing the short.


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## Yakkum (Dec 17, 2000)

okay, well its not the power button on the front cuz even if that were busted then i would still be able to get a power light on the motherboard.

My guess is either the motherboard is dead or the power supply. I unfortunately don't have spare crap sitting around to try different things. I guess I'll probably have to bring it into my local shop and see if they can test stuff for me.


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## Yakkum (Dec 17, 2000)

Oh yeah, and is there an easy way to test the power supply (without separate computer)?


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## MustBNuts (Aug 21, 2003)

Actually, the wiring that goes from the power button to the mobo is not soldered on...they are attached with pins. When you install you have to physically connect the wires to the mobo, so if while tooling inside the machine you accidentally pulled them off their pins, you won't see anything - no lights, no nothing.....

MBN

PS: You can remove/replace a power supply independently of the rest of the components, so if you had another one around, you could pop it in and test.


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## Yakkum (Dec 17, 2000)

Yes, I know how the power button attaches to the motherboard, however, my particular motherboard has a LED light on it near the bottom that is always on when there is power running to it and this was the light to which I was referring, not one of the other "power on" lights on the front of the computer case. 


Thanks for the help though.


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## tribe (Feb 10, 2004)

Alright, got back from testing everything out at my cousins (swapping processors) and I found out my cpu works in his mobo and his wont work in mine and they are both compatible. So that leaves one thing, my mobo is the problem. I even took out the mobo and tested it to make sure there weren't any shortage and still the same problem. So I am left to go out and buy a new one. 

Any suggestions? I had a Gigabyte 7vrxp, its kt333, so Im looking to something similar since I don't want to do a huge upgrade, just something small. I have been looking at the nforce boards and they seem really nice. THANKS


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## Rusty1952 (Mar 25, 2003)

Hang on there Tribe....unless i missed somethin or u left some details out....and befor u dash out and buy a new MB, i wanted to ask you if you hav tried powering ur systm on after unplugging all the pwr connectors to all of ur disk drv's ? If you havn't tried that you need to cuz there is the small possibility that one of ur disk drv's may hav recently developed a short and if so that'll shut down ur psu within just a second or two of powring up the pc.
Try that if u havn't.


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## tribe (Feb 10, 2004)

I have tried everything. When I tested it with my cousin's pc I only had the essentials; cpu, psu, mobo and memory. But thanks for looking out for me


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## Rusty1952 (Mar 25, 2003)

Gotcha ! Just wanted to make sure u weren't ovrlookin that small but important detail......

You said u weren't really lookin for a huge upgrade and u were interested in the Nforce chipst. I've only had it for a week but i just bought a refurb. MSI K7N2 Delta MB w/Dual Channel off of Newegg for just $45 and i got everything with the board as if it were a new one. Tickled me, cuz everyone wants bout $75 for a new one. So far it seems stable as a rock. Tomorrow i should be gettin a Barton 2800 to pair it with. Right now i'm just runnin it with a 800 Duron o'clocked to 882 Mhz. Stable with no freezes.
You might wanna look into it, although i can't vouch as to whether u'd get one complete like mine was. I may guess i was just lucky.


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## Ash_11 (Sep 19, 2002)

I went on a call last week with the same symptoms. The guy accidently turned the on/off switch to off on the rear of the powersupply. Not sure if yours has one, but it's worth a check. Sometimes, it's the simple things.


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## Yakkum (Dec 17, 2000)

Yeah, thanks for the help attempts guys. I am still out of luck right now though. 

I know about the switch on the back of the power supply. 

I am going to RMA the motherboard, since it is only a week old, and get a new one. Hopefully that will solve the problem. If not, well then I guess I'll try a new PS. 

Thanks again.


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## chewie1012 (Dec 27, 2001)

What happens when you put power to the power supply and turn the switch on? Does the fan spin at all, even a bit. What about a cdrom? Can you get power to open the cd rom? Maybe it is the power supply. When I first got into this business I was told power supplies go bad more than anything else in computers. Don't know if that is true or not but I have replaced more power supplies than anything else except cd roms.
Jerry


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## flytape8490 (Oct 7, 2003)

Howd you post with no motherboard to make the comp work? ;-?


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## Yakkum (Dec 17, 2000)

> Howd you post with no motherboard to make the comp work? ;-?


Umm, I don't know what made you think I could post. Or maybe you weren't referring to me. I don't know, but I couldn't get anything working. 
EDIT: or maybe you were curious because I am able to post here? Anyway, I have a laptop that I'm on now and there is another functional computer in my house as well. It's my third one (my project) that's giving me trouble.



> What happens when you put power to the power supply and turn the switch on? Does the fan spin at all, even a bit. What about a cdrom? Can you get power to open the cd rom? Maybe it is the power supply. When I first got into this business I was told power supplies go bad more than anything else in computers. Don't know if that is true or not but I have replaced more power supplies than anything else except cd roms.
> Jerry


Well I don't know how to get the cd rom or anything power without the motherboard. I wanted to just check to see if I could get a fan spinning or something, but the power supply doesn't kick in all those connectors until it gets a signal that the computer is powering up from the motherboard.

If you connect just a fan or drive to a power supply and nothing else at all, how would you suggest I turn them on? There needs to be that other intermediary to tell power supply its time to get going, right???


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## chewie1012 (Dec 27, 2001)

I could be wrong? But I think if you plug a power connector to the cd rom drive without any other connectors and turn on the power supply with it connected to the motherboard you should be able to see if power is going to the motherboard. Try it with the power supply not connected to the mobo. See if you get power. Then connect it to the mobo and see if you get power. If these don't work. Carefully pull the power supply from the other computer and see if it works. If is close in power. You wouldn't want to run an amd on a 250 watt power supply for long. You can see if it boots though. That way you don't have to buy a new power supply until you find out if it is bad or if its the mobo.
Jerry


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