New PC Build Won't Power On - Yet another one!!

Hi all,

I'm tearing my hair out in the middle of the night as I've been working on this new PC all evening!

I've built up my new machine and come to turn on for the first time and nothing........ I'm at a loss!

First of all, I've built PC's before and never had any problem so this is new territory for me somewhat! I'll lay out the steps I've taken and if anyone can suggest something I haven't done, please let me know!

1) Fully assembled new PC build won't power on. After pushing the power on button, lights briefly illuminated before going out and then nothing. I disconnected the hard disk and DVD-drive and removed the graphics card leaving just the CPU installed.

2) Verified large power connector to mobo is fitted as well as the smaller 4 pin one. Upon turning on PSU, a green light on mobo appears indicating power is indeed being supplied to the mobo.

3) I then thought it could be a faulty switch on the case I've tried removing all headers and using a jumper to short the power on pins as well as using the Reset button instead, all to no avail.

I'm now at a total loss! I've got the absolute minimum installed, but despite the fact the green mobo light is telling me there's power to the board, nothing is working, no fans are on, diddly squat.

Anyone got any ideas???

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  1. Sounds like a faulty mobo. possibly static discharge upon installation. Had it happen to me once on a MSI mobo P6N board. Exact same problem. Solution was, Mobo was warrantied..
  2. Hmm, I'm gradually having to admit to myself this is the problem :-( I can't find anything else that could be wrong with it. Such a shame really I finally got the last component yesterday after having had the other parts for a few months and then this happens.... Hope it's still covered under warranty!
  3. This is what you should do before you ever even mount the board.
    Take it out of the case, put in the CPU, 1 stick of memory, and the video card....see if you can get it to post outside the case.
  4. Yeah just done that, still nothing despite a brief moment of power :-( It's almost as if something is shorting somewhere causing the power to shut off
  5. That green light is misleading. All it means is the the relatively low current 5Vsb (standby) is active. It does not mean that the main 3.3, 5, and 12 volt outputs are present. There is also a control signal called "PowerOK" from the PSU that is supposed to go to a 5 volt logic HIGH after you press the power switch. The CPU needs this to boot. Losing this signal (like for example, if the PSU detects a fault shortly after powerup) will forcibly reset the CPU. All of this matches your symptoms.

    My first suggestion is to replace the PSU with a kown good one - or at least another.

    If that doesn't work, try this:
  6. Ok sounds good. I don't have a spare power supply at home so I guess it means taking it into work tomorrow where we have some spares and try one of those out...

    Will report back with any news!
  7. will you please post your full system specs?
    then we can give you more specific answers to help you with your problem

    most things you said point towards a faulty mobo though...
  8. sounds like the board has gone bye bye.
  9. Specs of the parts I'm trying to at least get going on their own:

    CPU is Intel Core 2 Quad, 2.4GHz, Mobo is ASUS P5K-E, PSU is Seasonic S12 II 500W.
  10. Ok, tried out a known good PSU on the motherboard and still nothing. Tried shorting the Power On pin (green lead) on the ATX connector and low and behold the PSU fan turns on so I've concluded my PSU is good. Looks like it's RMA time for the mobo. Thanks for all your suggestions! At least they proved I wasn't going mad!
  11. This is a longshot, but I once got a mobo that had the bios reset jumper installed on the reset side (out of the box). I nearly smashed things before I accidentally found it. After moving the jumper over, it booted smooth. :??:
  12. Yeah cleared the BIOS and reset the jumper back to where it should be but didn't work :-( Last thing I'm gonna check before mailing it back for a return is that no fuses are blown on it or anything
  13. baddog1: nasty ...
  14. Someone has just mentioned to me that perhaps the motherboard is not pulling down the power supply pin sufficiently to turn on? Does anyone know of this phenomena? I think some research is required this afternoon on Wiki!
  15. You tried another power supply and it didn't work either, so I suspect it is something else.
    You could try the suspect power supply on another system to see it turns on.
  16. More likely faulty, or uncompatible ram, then a bad mobo. What is the specs of your ram? Have you assembled you parts out of the system to be sure there isn't a short? Did you use the right amount of standoffs in your case and put then in the right spot? Did the standoffs come with paper washers, and if so did you use them? I hate to see you send back a mobo before everything has ben checked. Take your time and try to assemble outside the case with only one stick of ram. Double check the standoffs. What heatsink did you use? Did you take the plastic off of the heatsink? Its happened before. I dont think your dumb, I would just like you to get your pimp machine running today.
  17. My colleague at work has the same mobo and RAM so I'm fairly sure it's not a compatibility issue. It's GeIL 2GB (2x1GB) PC2-6400C4 800MHz. Out of interest, surely the system would at least power up the CPU fan even if the RAM was incorrectly installed or just bad? I've already tried assembling the system outside the case to no avail. Removed the CPU heatsink, CPU and cleaned and re-installed again. I have to admit that I didn't use the paper washers on the top of the stand offs initially but since the screwholes are grounded anyway, I figured it was ok to omit them but have since installed them to be sure.

    I think I've pretty much satisfied myself the mobo is dead. The final check someone suggested was shorting the PSU Good signal on the ATX connector to ground and see if it comes to life but I'm fairly sure it won't.
  18. Have you tried using diff memory? Try a diff stick. I also agree about the static discharge. Alot of people do not belive this can ruin hardware when in fact it can. If trying a diff stick does not work,then i would RMA the board. Always touch something metal before handling hardware.With winter here theres always more static.I have had so many customers ruin vidio cards because of this.They just will not listen.
  19. Had a similar problem with my ASUS p5w DH. For me it was a faulty USB connector/adaptor (one of thise blue plugs that came with the Kit) - I found it after 2 days of disconnecting each individual component and connector (drives, memory etc etc).

    If you haven't already done so I would begin to eliminate components one by one until you get down to the bare min. config
  20. If the Ram is faulty it will behave the way that you are having. I'd try a different stick of ram, and then send the board back if it don't work.
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