I’ll think on your problem a bit let you know if I do or don’t come up with something.
Is this an Emachine? That company likes to use equipment in ways you wouldn’t expect.
I’ve heard that some motherboards made recently have bad capacitors that cause weird problems. Check the caps for stuff leaking out, loose soldering, stuff like that. If your warranty is expired and you know something about electronics repair, you could try replacing them.
It is an eMachine, yes, although the hardware build looks fairly ordinary (unlike, say, a Gateway machine I tried to break down for components)
Sometimes companys like Dell or Gateway use nonstandard PSUs and mobos with unique pinouts and you can fark the mobo if you connect a standard one… but that’s neither here nor there, because it was working when you sent her home with it.
The real reason for my post is to MPSIMS this up a little and sympathise because I’ve also fix people’s 'puters for free then caught hell afterwards.
My guess is she did something she’s not telling you about.
Good luck.
Under different circumstances, I would be inclined to suspect that something was done by the user, however, I think in this particular case, she’d have owned up.
Earthing the green wire on the PSU starts the PSU fan going (and presumably supplies power to the MoBo), but still no life from the machine. Going to check again for shorts on the back of the board, but I’m starting to suspect that the mechanical vibration of the journey home has just killed some small but key component that was on the verge of failure anyway.
It was clear on the Specs page that it was an Emachine. That is once you focus on the header graphic that ads trains you to ignore in a browser. I wish I could say I thought of some thing new last night. I have to give this problem a R.I.P. heading and move on.
I concur; the new MoBo has just arrived; time for the fun to start.
OK, I’ve installed the new motherboard and… nothing… there’s no response at all; not even a power LED this time… what the heck is happening? Two failed PSUs?
The power led might just be the wrong polarity. Change the two wires around. You’re still stuck with it not working, but know if it’s the same problem.
This is weird; I went out and bought a new PSU (I’ll need one sooner or later anyway); still no joy, but with this one (and not with the others) I can get the CPU fan to spin up (as well as the fan in the PSU, obviously) when I earth the green cable on the main connector.
I did wonder about the LED polarity, but it doesn’t make any difference; the machine still won’t boot even with the LEDs completely disconnected.
This doesn’t make any sense at all; about the only thing I haven’t swapped out it s the CPU - could a duff CPU actually stop the machine from performing POST?
I said that a fried CPU could stop the board from doing anything.
Hmmmm…what should happen if I power up with no CPU installed? Shouldn’t I get at least an error beep from the Motherboard?
I don’t knw about the no CPU boot thing. I wold think no , but yu can remove a CPU from a working unit and try it. The best test is to swap in a different CPU, but then you risk fryng that CPU.
- Did you set all the new boards jumpers correctly?
- Give the bios a a manual reset.
- Try the CPU swap.
Yes, a defective –or mis-seated– CPU can cause precisely the problem you describe: the PSU activates and the power light comes on, but the motherboard can’t complete its pre-boot initialization. The PSU fan may activate continuously, momentarily or not at all.
That’s why I suggested reseating the slots. There aren’t many problems that keep a motherboard from even initializing enough to turn off the PSU. 90% of the time, it’s either a mis-seated component or a wanky PSU. I find the AGP, CPU and NIC to be the biggest offenders, but that’s probably not universal. I’ve never had this porblem with a socketed CPU, but the principle is the same.
I had one computer with a PPGA CPU mounted in a “slotket” adapter (It was one of the most used computers in my house–in addition to the usual stuff, it had “home entertainment” functions like digital recording and an HDTV tuner). Every 3-6 months it would hang on pre-init power-up, exactly as yours did, and sometimes needed as many as 3-4 cycles of jiggling, removing and reseating to appease it. Then it would be good for another 3=6 months of 8 hours a day use. Aside from that quirk, it was a great little computer, where otherwise incompatible AV cards lived in harmony, and its orderly wake-up from hibernation (we often used it as a digital VCR) would be envied by any of those disgusting Disney cartoons where birds tweet the joys of morning chores (Sorry – even after 20+ years of rising before dawn, I’m still a grumbling groggy teenager at heart. Morning people must die…)
I’m with the rest of the crowd: I bet that the trip home either (a) jostled the heatsink off the CPU, or (b) jostled the CPU out of whack. Take the heatsink off and have a butcher’s – is the top of the CPU scratched, charred, or otherwise visibly… wrong?
Also, incidentally, what kind of CPU is it, and if you know, what’s the eMachines model number? We can go Google and see if that model has systemic problems related to a too-heavy heat sink shaking loose. Regardless, the current CPU is suspect until you can check it in a different motherboard (pricey!) and the current motherboard is suspect until you can check it against a known-good CPU (pricey!). I don’t envy you, but I’m curious about what you find from here out.
Not that this helps you directly, but my aunt has an eMachine tower with a similar problem - when it’s plugged in, the fans spin up and the power light comes on, but nothing else works. Pushing the power button does nothing and it seems to sink much farther into the case than it should. Knowing nothing about PC hardware repair, I told her it was probably fried. I’ll ask her if she got it fixed or just bought a new computer. With her, chances are she hasn’t done anything.
Mangetout
A hard drive that has a boot sector going bad, can hang the computer for 2 or 3 minutes. I wasn’r quite ready to attribute the condition to a dying hard drive, but soon I really won’t be able to help. I hope this issue is resolved in the near future. Good Luck.
I can’t tell you all how useful this thread has been for me. I’m stuck in almost exactly the same boat as Mangetout, with a few small variations.
I had a PIII-based PC, built it myself, no problems for the past 2 years (which is why I’ve never been in a big hurry to upgrade.) A spring failed on the heatsink on the Northbridge chip and it cooked - dead MB.
Figuring this was a perfect time to upgrade, I bought a Matsonic MB (MS9127C) and an Intel Celeron chip and a gig of DDR PC3200 RAM.
On the old MB, I was using a Kingston ethernet card, a Matrox dual-head AGP video card, and a Creative sound card. The Matsonic MB has ethernet and sound onboard, so I didn’t reinstall those; I am using the Matrox video though.
After everything was installed, I booted up and the first time boot naturally went into the BIOS config. Everything there went smoothly, and the computer booted normally. then WinXP did it’s thing, finding all the “new” hardware and installing drivers. The new hardware installation seemed to go pretty well and the OS called for a restart, as it usually does. I clicked OK to restart - and the computer never rebooted. It was powered up for all of five minutes.
Now, I’m having the EXACT same problem as Mangetout. I hit the power button, the fans kick on, the LEDs on the front panel flash on, and then everything goes OUT. Dead. I’m working through some of the suggestions in this thread and I’m grateful for them all. I’ve been building and working on computers for 14+ years and this is the first time I’ve ever been completely stumped. I’ve got to run out for a new PS later today - it’s the only thing that I haven’t tried.
Mangetout, keep me informed, please, and if I come up with a solution on this end I’ll do the same.
thx.
FWIW, my problem is solved. It was, indeed, the power supply. Replaced it this afternoon and all is well.
Hope whatever you’ve tried has worked for you as well, Mangetout.