System won't turn on... even after new parts


I am working on a computer I built a little over a year ago for a customer. About a week ago the owner says it just would not turn on at all. He wanted it fixed, and for some new upgrades to be installed. I looked at it and it seemed like the PSU was dead, but even when I tried it with a tester PSU it still wouldn't come on. I unplugged ALL peripherals, and removed and re-seated the video, sound, and RAM. After that didn't work I tried unplugging every thing including the optical drives and HDD... still wouldn't turn on with just CPU and RAM installed. (usually it will at least turn on with just that even if it gives you error beeps) I checked to see if anything was grounding the mobo or anything else, there are no blown capacitors, I reset the BIOS by pulling the CMOS battery, still nothing. We've already ruled out the power switch by pulling the case leads and using a flat head screw driver to make contact on the power jumpers, and we replaced the power cord from the wall the to PSU. (yes, there was power to the wall socket, it was plugged in, and the power switch on the PSU was ON ;) lol) I also pulled everything out of the case and assembled it thinking maybe the case was somehow grounding it. When you turn off the system you hear that faint kinda pitched power down noise that you hear sometimes when you pull the power cord and press the power button to drain residual charge from the board... so I know it's getting power. (if your a tech you'll know what I'm talking about) After all this I ordered a new PSU, motherboard, video card, and CPU as upgrades/replacements. (I thought that the mobo or CPU was dead) Now, even with a new CPU, new Mobo, new PSU, and new video card... IT STILL WON'T POWER ON! Oh, and then I even repeated all of the above steps with the new parts. ANY SUGGESTIONS? I'm at my wit's end!
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  1. Check the power on switch behind the case front panel. Bad switch possibility.
  2. I thought of that so I pulled the case's jumper wires and used a flat head screw driver to make contact between the power jumpers on the old an new mobo... nothing. (that always, er usually... works)
  3. Have you tried assembling it out of the case yet?
  4. Yup, did that. Pulled EVERYTHING out of the case and put it together thinking that maybe the case was grounding it or the power switch/leads were bad. No go... :(
  5. I think it's gotta be a faulty case switch. Maybe a wire is broken or it isn't plugged in correctly. Maybe the reset button is sticking or something.
  6. it's not the switch... I pulled all the case leads from the mobo and used a flat head screw driver to make contact on the power jumpers on the mobo (old tech trick that has worked for years to rule out power switches... or if you assemble it out of the case)
  7. You said the old PSU appeared dead. Does this one spin up when you connect power? Have you tried jumpstarting it outside of the case? When you say the system doesn't power up, you mean no fans start up, no LEDs, no HDs?
  8. What you have is two systems with what is likely Bad MB's. Or. You have hooked both MB's to a PSU that is defective and damaged both MBs. You could let the customer have your 6800 rig as a loaner :D
  9. Ah yes, maybe he hooked up the new mobo to the old PSU to try it. That would be bad :(

    If not, the only other common element I see is the RAM. Hey, you're a tech.. test the new parts individually :D
  10. Quote:
    Ah yes, maybe he hooked up the new mobo to the old PSU to try it. That would be bad :(

    If not, the only other common element I see is the RAM. Hey, you're a tech.. test the new parts individually :D

    Well I said I thought the old PSU was dead... but I never got to hook it up to a multimeter. (mine unfortunatly has turned up missing :( ) and NO, nothing comes on at all... no lights, no fans jump, no HDD noise... NADA. Oh... I did not hook the new mobo up to the old PSU. I did that years ago and learned my lesson. LOL I thought about the RAM too but usually RAM will not stop a machine from turning on all together... it might stop it from POSTing, but not from powering on at all. I already made plans to test each of the parts as soon as I get home so I'll let you know what happens there! :D

  11. Okay :D Don't rule out the RAM. It's the only lead we have right now 8O
  12. you're right... I do plan to test the RAM and everything else individually as soon as I get home... I just didn't think it could be it since I even tried it without the RAM installed. (without RAM it may not POST, but should at least power on the fans or something) I'm determined to figure this out!
  13. Am having same problems with a customers computer after a year as well strange...... Any way I am getting ready to purchase a new mobo soon, after a little more research, to try and solve this problem.
    please keep us up to date on your problem, sony3127??
  14. Of course I will WolfX... here' something that's even more strange to me though. A week before I got this system I'm talking about, I got a machine that wouldn't turn on but every once in a while. If you let it sit for a while unplugged and then plugged it back in... sometimes it would come on, sometimes it wouldn't. I haven't gotten it working properly yet, but when it does come on it works perfectly... you can even restart it with no problems. But if you turn it off all together, it won't turn back on for days... then, with nothing done it... it will start working again. It's not the power switch b/c I can and can't turn it off and on with just a screw driver touching the leads on the mobo... WEIRD HUH?
  15. So you've had two systems with weird power problems. Were they connected to the same wall socket/power outlet? Weird problem.. maybe requires a weird answer....
  16. Nope, they both were at thier owner's house (2 separate places) when the problems started. I also put my own system (yes, I put my own system at risk) on the same wall plug and power cord and it worked just fine.
  17. OK... you won't beleive this... remember I told you that I had removed EVERYTHING including the RAM and reseated it all blah, blah, blah? Well, after talking to you guys I went home and decided that I would only pull ONE of the two RAM sticks out and try it... IT TURNED ON. Then I said to myself... "Well, just to make sure let me put this one back in and try it again." So I put the second RAM stick in and it came on again! WTF? So it works now... but I really don't know what fixed it being that I already had removed that RAM before... just not one at a time. Now I'm hoping that the OTHER system that wasn't turning on is just a power switch or something so I'm gonna try that out tonight. But I'm REALLY confused and frustrated b/c I don't feel like I really fixed the problem... more like I just got lucky and it just started working. I wish could nail down the problem better so I know what to look for if I ever come across this problem again! 8O
  18. Hey now... lol... you saw I went through some pretty thorogh steps to troubleshoot this. Seriously though, the ONLY THING I did since the night before when it wasn't working was pull ONE RAM stick and try to fire it up... that's it... I didn't touch anything else. It wasn't working the night before, now BAM it works. So maybe it could have been human error... but nothing changed between the night before and the time I pulled that RAM stick. That room stays locked too so I know that noone else touched it. Oh well... AT LEAST IT WORKS NOW! :D
  19. Sounds to me like faulty RAM. I've got a stick of mushkin DDR ram that acts like that. Sometimes it will come on, sometimes wont without any beeps or peeps from mobo, but most of the time it will crash under heavier load. I would run memtest x86 for 24h and see what you get.

  20. Your shop has gremlins in it. I hope you didn't feed any of them after midnight....
  21. LOL @ Phreejak! That's possible! LOL Dammit GIZMO!!!!

    Well you could have a point there KOzOK... will run memtest this afternoon and check that out. Thanks for the tip. :)
  22. Umm maybe i have Gremlins as well not sure..... will try and remove the one stick of ram tonight and replace it with one that I now works and post.
  23. Well considering that one I recieved this computer it had not been dusted out in a year and was caked with dust everywhere, I'm thinking its going to be the mobo just waiting for the client to fork out some doe for a new one. Will let you know when this happens, memory swap did'nt not work :(

    Hard to find this mobo at a good price anymore not listed on newegg.

    GA-K8NS Ultra-939
  24. could have been a ram socket contact alignment problem or a piece of flish(old technical term) shorting traces that reinserting the ram cause the board to flex enough to work now.
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