DELL - PC wont boot unless CMOS is reset, HELP!

itsparsic

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I am currently fixing up my old DELL XPS 8700 computer after a few years without using it. Long story short, pressing the power button doesn't do anything to the pc, nothing happens...sometimes. Occasionally the pc will start with a delay after hitting the power but not frequently enough not to call this an issue. The only way to start the system reliably is to reset the CMOS either by removing and replacing the battery or shorting my reset pins. Additionally the sound has stopped working on my pc, no audio out of the front or rear IO. I have ordered a cheap sound card to get around this but I'd love to be able to start my PC more reliably. I have already troubleshooted everything I knew to try, Different PSU, Different drives, minimal RAM, different CMOS battery(Another used one, waiting on new batteries in the mail), updated BIOS, everything besides a full BIOS flash since I haven't figured out how to yet. My only thought now is to just rig my power button(or reset switch) up to my RESET CMOS pins to start it every time that way. Once my pc starts besides audio everything works completely fine and I have never experienced any other issues. (Board is a DELL 0KWVT8 as far as I know) Also the only other thing I can even think of is the board is shorting to the case somehow, but as far as I know I properly installed it and I have also switched cases and power buttons. I am fairly new to building pc's so this has surely baffled me, especially since it DOES work occasionally, any advice would be greatly appreciated. If it is a faulty board so be it, but since this is my old PC and I am fixing it up to give to a friend I'm not looking to spend anything for a replacement.
 
wait for the batteries. next time, you can pick up a 2 pack for $1 at the dollar store.
welcome to [H] too!
 
Update, I installed a new CMOS battery and the problem persists! I have no clue what's left to try besides a bios flash, I've already updated the bios too. I'll keep working on a fix though.
 
if a new battery didnt help, try everything outside the case to rule out your suspected short but if it still acts the same its the old mobo dying.
 
Check the mounting screws. If the screws that mount the motherboard are slightly too large at the head or even the standoff it is possible that over time they have worn through the soldermask of the board and contacted copper. There shouldnt be anything near those other than ground fill but who knows.

Blow the whole thing out too and give it a real good look over, cant find it now but i have a photo of a stripped screw thread contact welded across a set of pins.
 
Check the mounting screws. If the screws that mount the motherboard are slightly too large at the head or even the standoff it is possible that over time they have worn through the soldermask of the board and contacted copper. There shouldnt be anything near those other than ground fill but who knows.

Blow the whole thing out too and give it a real good look over, cant find it now but i have a photo of a stripped screw thread contact welded across a set of pins.
Thanks for the feedback, I'll have to try it out of the case and look for possible grounding problems. The PC DOES run though so I am skeptical about a possible short, when I turn my PSU on I also get lights on the board. I'll have to try it though and post an update afterward.
 
Definitely try it out of the case and see if you can debug it... but if not...

I dunno what dell does for switches (or if you're using the dell case anymore anyway), but a standard reset switch could definitely be repurposed as a cmos reset switch if all you've gotta do is reset that every time... but could you just pull the cmos battery and not put it back instead?
 
Yes bizarre case. I agree with those who posted above. Get the MB out and bare bones.
And good job on your efforts. Your trouble shooting logic is very good for someone who self stated, is fairly new to building pc's.
 
Definitely try it out of the case and see if you can debug it... but if not...

I dunno what dell does for switches (or if you're using the dell case anymore anyway), but a standard reset switch could definitely be repurposed as a cmos reset switch if all you've gotta do is reset that every time... but could you just pull the cmos battery and not put it back instead?
Thanks everyone for the advice first off. I'll be trying the pc out of the case in the next few hours now. As far as repurposing a reset switch for CMOS I could live with that, but besides the longer boot times I am concerned about the button being accidentally hit while the pc is running and the effects of resetting CMOS while in windows. After that I am also concerned about using a dying motherboard as I don't know if it will eventually kill my other components when it fully goes. (3 Drives, Disk Drive, GTX 960, Sound Card, & 16gb Ram, i7-4790) Any other advice regarding my concerns would also be greatly appreciated!
 
Thanks everyone for the advice first off. I'll be trying the pc out of the case in the next few hours now. As far as repurposing a reset switch for CMOS I could live with that, but besides the longer boot times I am concerned about the button being accidentally hit while the pc is running and the effects of resetting CMOS while in windows. After that I am also concerned about using a dying motherboard as I don't know if it will eventually kill my other components when it fully goes. (3 Drives, Disk Drive, GTX 960, Sound Card, & 16gb Ram, i7-4790) Any other advice regarding my concerns would also be greatly appreciated!
Yes test out of case and bare bones. One stick and one drive and iGPU. If that fails swaps stick then drive. I've had a PC that was all messed up because of one HDD before. Weird shit can happen and does. Good luck.
 
Yes test out of case and bare bones. One stick and one drive and iGPU. If that fails swaps stick then drive. I've had a PC that was all messed up because of one HDD before. Weird shit can happen and does. Good luck.
Haven't been able to build a test bench yet but after a thorough inspection of the top of the board I've found 2 capacitors which are touching each other, not sure if this could be the cause of anything since they look shielded but it's worth a mention.
 

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Haven't been able to build a test bench yet but after a thorough inspection of the top of the board I've found 2 capacitors which are touching each other, not sure if this could be the cause of anything since they look shielded but it's worth a mention.
Also a lot of the capacitors around this area are on a bit of an angle, I have no way of knowing if it's always been like this or not. I've been stress testing the pc by running games non stop and I've been doing so for 4 hours now without any issues, this issue really seems to just stop with the audio problem and boot.
 
Also a lot of the capacitors around this area are on a bit of an angle, I have no way of knowing if it's always been like this or not. I've been stress testing the pc by running games non stop and I've been doing so for 4 hours now without any issues, this issue really seems to just stop with the audio problem and boot.
look under the caps to make sure they arent leaking, also check if any are bulging at the top.
 
look under the caps to make sure they arent leaking, also check if any are bulging at the top.
There are no leaking or bulging caps anywhere on the board from what I can tell, I also gently bent those two touching capacitors off of each other. I have it setup on a test bench now on my new MB box. Running iGraphics with a single SSD drive with Windows. Knock on wood, it's working fine now. It really could have been just a short since I have tested it in the case with the same setup with no changes before. The Audio still doesn't work which is fine by me since I did order that Audio card coming in the mail today. I'll have to figure out how to re-install the board without letting it short anymore, the cause must be something like what Darunion said. As far as the not working Audio I do hope that doesn't mean the board is still on it's last legs, I hope I can get another year or two out of it, the pc will be rarely used either way (Once a week) Thanks for all the help and I would still appreciate any suggestions on how to rebuild this without causing this annoying short again.
 
what are you using for power/reset out side the case, just shorting the pins? if so the case buttons themselves could be and issue. ive seen power buttons that stick and will power up a system, stick and then cause it to power off again.
 
what are you using for power/reset out side the case, just shorting the pins? if so the case buttons themselves could be and issue. ive seen power buttons that stick and will power up a system, stick and then cause it to power off again.
I'm currently building back into my case and have the motherboard sitting on the standoffs, it's starting fine but when I put the screws in it shorts and stops turning on. I just found some black coated screws that might work instead so I'll give them a try, hoping the paint doesn't allow any short to happen. I am using my old power switch right now but both the old and new switch work fine. Any other ideas on how to stop the shorting would be appreciated, thanks.
 
I'm currently building back into my case and have the motherboard sitting on the standoffs, it's starting fine but when I put the screws in it shorts and stops turning on. I just found some black coated screws that might work instead so I'll give them a try, hoping the paint doesn't allow any short to happen. I am using my old power switch right now but both the old and new switch work fine. Any other ideas on how to stop the shorting would be appreciated, thanks.
paper washers. cases used to come with them. could even just cut some squares of craft paper and jam the screw through...
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paper washers. cases used to come with them. could even just cut some squares of craft paper and jam the screw through...
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I have been working on this fix for so long I am hesitant to claim it's fixed but after I used those black coated screws(only had 5 of 6 standoffs) It seems to be starting fine. My best guess is this short/ground might be the cause of the audio failure which wont be coming back. I may have to try the paper washer idea for the last standoff if I choose to use all 6 screws. Thank you everyone for the help here, this was my first project PC besides building my new PC 2 years back and it has sure been educational. A short was the last thing I thought it could be especially since the pc did run!.. I hope I won't have to post anymore here and that it will stay fixed but I'll have to continue the assembly now and see how far I can get...hopefully all the way!
 
I would use the washers that pendragon suggested, i like nylon but that will likely need longer screws. The painted screws will chew through that coating after enough vibration.

Actually that screw hole in the bottom left of your photo, those traces look dangerously too close to where a screw head would go. maybe check where the screws are actually at for a similarly looking issue.
 
I'm going to continue the build today with the black bolts on the board and get the whole thing assembled, after I'm done I'll look into getting/ making those plastic or paper washers, I just want to get it working. Funny enough plugging everything in so far I've found one USB from the front IO which when plugged in shorts the board again. I'll just leave that unplugged for now since I already have enough of them. Also that screw hole in the bottom left of that picture, as far as I know has never held a screw, I only put them in the marked holes, if you could call them that. I'll attach a picture showing what I have built so far, notice that bottom left mounting hole is missing its screw as I only had 5 of them with black coating. Thanks again for the help, you're making this nightmare of a build a lot easier for me.
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No prob, glad you found your issue. It is a pain taking it all apart and going piece by piece but often becomes the best way to work through it. Also thanks for putting up your process, helps when someone else stumbles across it to get ideas from.
 
Haven't been able to build a test bench yet but after a thorough inspection of the top of the board I've found 2 capacitors which are touching each other, not sure if this could be the cause of anything since they look shielded but it's worth a mention.
Build a test bench? It is putting it on top of the MB box it came in ;)
Welcome to the club bro :)
 
Build a test bench? It is putting it on top of the MB box it came in ;)
Welcome to the club bro :)
After the fact I can now admit, "I haven't been able to build a test bench" more translated to, "I've been avoiding tearing apart the entire computer again for the 3rd time, but I will soon..." Haha, thanks!
 
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