PC troubleshooting sanity check

So, got my new components and assembled them today. The system won't power up. Here are the symptoms and what I did.

First, everything attached and all power cables and connectors hooked up. Attached power cord and switched ps to 1. Mobo LED did not light. Pushing power button on case gave no change.

Flipped 2-pin connector for power switch. No effect. Put back to original orientation.

Pulled 24-pin power block and plugged into 20-pin power tester. All lights green. Plugged in 4 pin block - no result. Same for other 4-pin block. I think the 4 pin tester is dead.

With the 20 pin connecter hooked up to the tester, pushed power button on chassis. Fans turn and disks spin. But the cpu fan did not spin, I don't think. Powered off and unplugged.

Started pulling components out of the system. Stripped down to mobo, cpu and memory. Plug in system and now the mobo LED lights. But power switch does not work.

Pulled memory. Still no go.

Replaced power supply with new one. Same results.

I think I'm looking at a bad mobo. Any ideas? Suggestions for safely removing the heat sink from the cpu? I'm dreading that.

Thanks for any ideas.

No videocard will usually prevent a system from booting.. you'll get some beeps but nothing more.

To me it sounds like you either have a bad motherboard or perhaps a short somewhere.. sometimes the brass standoffs are incorrectly on or not on and you get a short.

not sure what you mean by the 2 Pin power connector for switch.. do you mean the Power Supply fan power? Usually the AUX power cable from new motherboards is usually 4 pin or 8 pin.

Got no beeps. The two pin is just the wire pair that connects the front switch to the mobo. I was worried it might be inverted, although I doubt that would really matter.

I guess I can redo the standoffs. How would I know if it's the cpu? Wouldn't that produce a beep, that is, it would not prevent the system from powering up?

Yep. Took it all the way down and re-screwed the standoffs, checked the frame for warpage, used a piece of paper after mounting to check for contact between the mobo and the mount plate. Nothing seems to be shorted. Still the same results.

I didn't remove the cpu because frankly I'm not sure of the best way to do it. I guess just yank it up and then slide it off the heat sink? Any advice on that? Socket 939 with stock heat sink.

I'll call ASUS on Monday. Anyone know how they are for warranty returns?

Thanks.

Ah...one more thought; I had a similar problem about 4 years ago with a new motherboard- there was a tricky sequence of powering up the motherboard. I looked at www.sharkeyextreme.com for some technical notes in their forums.

Oh one more thought- maybe their is a conflict between the video card and the "on-board" video? Try it without the card first to see about that.? Though it sounds as if you might have already looked at that angle.

Wow... I guess we jinxed it by talking about "annoying" troubleshooting the other night. First off, yes, the power switch has two cables (2-pin). One is positive, and the other is a negative/ground (I forgot which), and shouldn't work if it's backwards. Normally it's labelled on the board, though it normally takes a magnifying glass to see it. Also check the manual to make sure you've got the +/- pins right.

I'm not sure if you did this with the paper, but try taking the mobo out of the case, and putting it on the anti-static bag it came in. If it's a problem with the case, that'll solve your problem.

I've also heard that faulty wires could be the problem. One guy said his system did this and his reset button was shot. Try only connecting the power switch and see what happens. If it works by itself, try adding cables to see what doesn't work.

And one last thing. If your power supply has that little 115/230 switch in the back, make sure it's set to what your mobo needs. It's a little silly, but I've made that mistake once or twice.

Good luck man.

BTW, sorry I didn't return your call. I didn't get the message till just now, and it's a little late to be callin' anyone in my opinion (not to mention, I'm on my way to bed). I'll call ya tomarrow, or I might just swing by after I get some stuff done.

Right. Only thing of those last few suggestions I've not done is the boot-on-bag. I basically did a disconnect-and-try cascade with the various wires and cards, as best I could.

The more I think about it, the more the lack of any beeps concerns me. (Yes, I've flipped the speaker cable too.) With a good mobo, I should first get a long beep indicating power is on. I'm not getting anything, and I've never seen the cpu fan spin.

That's what leads me to believe it's not the memory or cpu or like that.

I may pull the reset sw connector just for grins, make sure I did that. But I think Monday I'm gonna call ASUS.

Well, looks like the front power switch is indeed dead. Go figure. I guess I'll get that fixed and move on to the next step.

I ended up sticking the wires together inside the wrap that failed, then using a blob of superglue to hold it all in place. That worked; the system is up and running. Just installed Oblivion - it self-detected and set the graphics to "Ultra High".

Robear wrote:

I ended up sticking the wires together inside the wrap that failed, then using a blob of superglue to hold it all in place. That worked; the system is up and running. Just installed Oblivion - it self-detected and set the graphics to "Ultra High". :-)

Robear Translater wrote:

MUAHAHA!!! My evil system is up and running, and will pwn you all! Yes, someone attempted to sabotage my plan by sending my case with a broken power switch, but the attempt was feeble at best! It's processing power will outcalculate even the most formidal of opponents, and my GPU will generate polygons of numbers your systems can only imagine! DIE N00BEHS!!!

*clears throat*

Yeah, it's sweet.

Just to be clear - after all this, it was your actual physical power switch that was F'd? That's a first. Stone dead systems (I've had a few) have almost always been unfixable core motherboard problems. I guess that's an object lesson for future hair pulling in my basement.

rabbit wrote:

Just to be clear - after all this, it was your actual physical power switch that was F'd? That's a first. Stone dead systems (I've had a few) have almost always been unfixable core motherboard problems. I guess that's an object lesson for future hair pulling in my basement.

Yeah, I talked to him over the phone and suggested we start with the switch, and I brought one of my empty cases over. I honestly didn't think it would do anything (I've gotten bad power supplies, but never a bad switch), but it was worth checkin' anyway, just to be sure we covered everything. After we realized the switch was dead, he pulled it outta the system and only the negative cable was even hooked up... the positive had been ripped outta the socket.

And since it was a solderless connection, and there was a plastic sleeve on the wire, and a plastic rim around the connector, it was too tight to easily solder. I see why they use the shrink wrap. I figured I would just replace the switch itself, but the local Radio Shack has had it's electronic parts section emasculated - a whole wall display of soldering irons and one vertical stack of components to actually solder.

So after I struck out, I thought about those components you see sealed in plastic, and started eyeing the superglue.

I'll replace it eventually, but it's running just fine now.

Congratulations; I have to say that's a "first" for troubleshooting for a problem like that that I've heard of....the Power Switch, not assembled correctly....maybe a plot to drive IT guys crazy?

Wow. That is a first for me, too. Good catch, guys.

It took two of us, and all I can say is, cyanoacrylates are your friends.

Congrats on finding the problem, I too would have probably never thought of checking the power button on the case for damage, and I have been taught when trouble shooting always work from the easiest problems on up to the harder ones. It saves you a lot of headaches.

It's added to the list now. Sigh. Works great now, however. Still loading software in the evenings.

So your power switch on your case was bad? Did you RMA the case and get a new one?

With power problems, that's usually one of the things I check, but I've only come across a bad switch once ever in like 8 years. For future reference, a quick way to test if it's the power switch itself that's dead you can use just a plain old jumper on the "Power Switch" pins on the motherboard. When you hit the power button, all it's doing is sending a brief signal through the pins, so you can simulate the same thing. Just hold the jumper with some needle nose pliers, quickly slip the jumper on and remove it and the system should turn on.

So your power switch on your case was bad? Did you RMA the case and get a new one?

Since it was just a loose wire, I fixed it with the superglue and sent an email requesting a new switch. No reply yet, I'll probably call them in the next few days.

Just hold the jumper with some needle nose pliers, quickly slip the jumper on and remove it and the system should turn on.

It was an idea I had, but ASUS warns in their documentation that this can lead to serious damage, so I decided not to try it (Purevil was pretty adamant about that too lol).

Vega wrote:

With power problems, that's usually one of the things I check, but I've only come across a bad switch once ever in like 8 years. For future reference, a quick way to test if it's the power switch itself that's dead you can use just a plain old jumper on the "Power Switch" pins on the motherboard. When you hit the power button, all it's doing is sending a brief signal through the pins, so you can simulate the same thing. Just hold the jumper with some needle nose pliers, quickly slip the jumper on and remove it and the system should turn on.

Robear had suggested we do that, but I've never done it (and had never heard of anyone else doing it), so I just used a switch I knew worked. Granted, using a jumper would have been a lot easier than lugging an old case around (no way to take the switch out), but it was safer in my mind to use a route I knew would work and not damage the board.

Thanks for the info though. I'll definately remember that.

Ya, I suppose technically there's a potential of a static discharge which probably wouldn't be good. But sticking a jumper on there shouldn't hurt anything. They make you hold the power button in for like 5 seconds or so to power off the PC.. which is the same as leaving a jumper on there for the same amount of time.

This problem (or those like it) is why my newest favorite motherboard feature is on-board power/reset switches. You can build the entire box up without the.. well box.

Glad you got it sorted out.