PC won't POST . . .

[Noel 4,563]

For about 3 days I had sudden onset of random lockups. I'd reboot, and all would be well for a minute or two, then lock up. I checked all cards, cables, memory seating, etc, and had a successful login and session for about an hour. Turned it off, then next day, the single POST beep code that was always present and heralded a successful POST, disappeared, and she wouldn't boot up at all: no output to the monitor, no beeps, but all the lights were on, the CPU fan was running. I have a PC Power n Cooling PSS that is well overrated for my components. It's at little over 2y old along with the other parts. I have no way to test the CPU, nor the PSS. I did happen to have the exact same mainboard, so I swapped it out for another one, same behavior: no POST beeps, nothin' out to the monitor. I even put in an old EVGA 8800GT video card and took out my 280GTX. Nothin' helped. I think it's doubtful it the DIMMS--I swapped out each of two DIMMS, to see if having only one installed would fly, but again to no avail. I can say for sure, this deterioration began about 3 days ago and did not happen abruptly, all at once. The machine went from random lockups, interspered with an hour or two of flawless FSX performance, then no POST.So, I'm thinking it's either the CPU or the PSS. Kinda doubt the PSS, since we have power to everything, or so it seems. What's your best hunch? CPU? It was the best I could find at the time, and it's been wonderfully good 'nuf for FSX. It's been overclocked for about 1/3 of it's 2+y history (when not flying, would dual boot to standard 3.0Ghz), with vCore at 1.3625. Core temps were always under 60, and usually under 55 overclocked.Your thoughts are appreciated. Not sure where to go from here . . .Noel

[Crewecut 1]

I most definitely suspect a psu failure from what you're telling. No-name brands are not to be trusted. It may deliver some power, but not enough. If you do get it to life, try OCCT cpu stress test, and particulaly look at the graph for the 5V line.My advice is to get a well reviewed not-too-cheap psu.Bjorn

[Kosta 122]

PSU broken, worst case Mainboard blown. Probably nothing else. CPUs rarely die...In your situation, I'd take everything out, clean it, then build a comp outside of case and start ordering components one by one - starting with the PSU (you can easily test each if the computer is not in the case, and you won't be damaging/scratching the PSU if you are not putting it in the case).That's what I'd do.

[ryanbatc 13,050]

I most definitely suspect a psu failure from what you're telling. No-name brands are not to be trusted.

PC Power and Cooling is a very well known and quality brand.

[dazz 69]

What PC Power & Cooling exactly Noel?

[Guest jahman]

Disconnect the HDD and all peripherals. With only PSU, MB, RAM and Video try to boot and see of you get your POST codes back. If not, remove Video card and try again. If still no POST, remove all RAM modules and try again. When "trying again" always unplug PC from mains and wait a few minutes for internal voltages to drop. POST codes here (but your MB manual is the definitive source).Cheers,- jahman.

[Superpilotv2 2]

I have soemtimes the same problem with my PC. All lights and fans are running, but it won´t boot. This happens mosly when I try to get back online after the system went into sleep and I try toget it on again. My workarround is taking the BIOS battrey out, wait some time and then plug in the battery again. After this it boots again with zero problems (My oc is gone, but that´s not that difficult.).So you could maybe try this.

[Noel 4,563]

I most definitely suspect a psu failure from what you're telling. No-name brands are not to be trusted. It may deliver some power, but not enough. If you do get it to life, try OCCT cpu stress test, and particulaly look at the graph for the 5V line.My advice is to get a well reviewed not-too-cheap psu.Bjorn

Bjorn, I think you missed a salient part of my post: "PC Power n Cooling PSS" is what I have, with a 50a single 12v rail.

PSU broken, worst case Mainboard blown. Probably nothing else. CPUs rarely die...In your situation, I'd take everything out, clean it, then build a comp outside of case and start ordering components one by one - starting with the PSU (you can easily test each if the computer is not in the case, and you won't be damaging/scratching the PSU if you are not putting it in the case).That's what I'd do.

I swapped out mainboards and no change, so I have to effectively r/o Mainboard blown. From reading Anand's report on Yorkie processors, quite a few of the quads will die when subjected to overclocking potential heat and overvolting.

Disconnect the HDD and all peripherals. With only PSU, MB, RAM and Video try to boot and see of you get your POST codes back. If not, remove Video card and try again. If still no POST, remove all RAM modules and try again. When "trying again" always unplug PC from mains and wait a few minutes for internal voltages to drop. POST codes here (but your MB manual is the definitive source).Cheers,- jahman.

I have to say I never unplugged between changes. But I did do everything else on your suggested list.

[Guest jahman]

I have to say I never unplugged between changes. But I did do everything else on your suggested list.

Don't mess with the insides of your PC without unplugging it first! You should always:

1. Unplug your PC when taking the lid off for personal safety reasons.
2. Unplug all peripheral devices to avoid ground-loop induced voltages that could damage your PC's internal components.
3. Actively manage your environment to impede static build-up by raising the relative humidity of your room
4. Then ground yourself by touching an unpainted water pipe/fawcett/radiator (no walking allowed unless barefoot and no carpet!),
5. Then touch the case of the PC to bring the PC down to your potential,
6. and only then open the cas and touch internal components.

I once had a 1/2-inch spark fly from my fingertip (the dielectric resistance of air is 30 KV/cm, so "you do the math") when actuating a switch on one of my GoFlight modules that fried the module, so now I have a grounded metal strip next to my sim hardware that I always touch before I start simming.Remember, 5 volt logic gates fry at 6 volts (never mind 1 volt logic!). When you feel your hair standing-up ever so slightly due to static, your body potential is already tens of thousands of volts above the ground plane! (And if you're bald, you would never even know!) :-)Cheers,- jahman.

[Noel 4,563]

Don't mess with the insides of your PC without unplugging it first! You should always:

1. Unplug your PC when taking the lid off for personal safety reasons.
2. Unplug all peripheral devices to avoid ground-loop induced voltages that could damage your PC's internal components.
3. Actively manage your environment to impede static build-up by raising the relative humidity of your room
4. Then ground yourself by touching an unpainted water pipe/fawcett/radiator (no walking allowed unless barefoot and no carpet!),
5. Then touch the case of the PC to bring the PC down to your potential,
6. and only then open the cas and touch internal components.

I once had a 1/2-inch spark fly from my fingertip (the dielectric resistance of air is 30 KV/cm, so "you do the math") when actuating a switch on one of my GoFlight modules that fried the module, so now I have a grounded metal strip next to my sim hardware that I always touch before I start simming.Remember, 5 volt logic gates fry at 6 volts (never mind 1 volt logic!). When you feel your hair standing-up ever so slightly due to static, your body potential is already tens of thousands of volts above the ground plane! (And if you're bald, you would never even know!) :-)Cheers,- jahman.

You sound like you know the subject so what can I say. I remember reading it is best to keep your PSS plugged in, then touch the metal case when preparing to touch components, so as to equalize potentials (since your PC is connected to ground). Aren't components electrically isolated, relatively speaking, from the PC case? I've done this now for about 20y in doing all of my own work and assembling many PCs, and never had a problem that I am aware of. I am aware of conditions that generate static, and we are in a low risk environment currently where I live.Thank you for your insights though,Noel

[Kosta 122]

Jahman, your post to me sounds a bit like overreacting. I must say, you do sound like someone who knows what he's saying, but me also never ever had such problems with static or anything. I also open up the case if I want to exchange RAM or something. I rarely unplug. Only reason to unplug (and then I only flip the switch) is if I change the CPU or some card from the slot. Surely not for SATA, other power cords than mainboard etc...The only thing which happens automatically is that I touch the case before I open it, of course... and even here I never had a spark or something.

[Guest jahman]

You sound like you know the subject so what can I say. I remember reading it is best to keep your PSS plugged in, then touch the metal case when preparing to touch components, so as to equalize potentials (since your PC is connected to ground). Aren't components electrically isolated, relatively speaking, from the PC case? I've done this now for about 20y in doing all of my own work and assembling many PCs, and never had a problem that I am aware of. I am aware of conditions that generate static, and we are in a low risk environment currently where I live.Thank you for your insights though,Noel

Blimey! You're right about the case being electrically isolated, so forget that bit and touch instead a part that isn't, like the ground prong of the PSU cable (please after you have unplugged it! :-) The problem with keeping your PC plugged in is of course your PSU is connected to the mains. Suppose your PC isn't booting because, unbeknownst to you, the PSU blew-up and is feeding mains voltage where it shouldn't. I once saw an electrician right after he shorted power with his arms from one hand to another (with a loud boom!). You don't forget the bits of skin dangling. The man was seriously burned. So always be cautious and respectful WRT mains power, especially since the precautions involved are actions that cost you nothing and all.

Jahman, your post to me sounds a bit like overreacting. I must say, you do sound like someone who knows what he's saying, but me also never ever had such problems with static or anything. I also open up the case if I want to exchange RAM or something. I rarely unplug. Only reason to unplug (and then I only flip the switch) is if I change the CPU or some card from the slot. Surely not for SATA, other power cords than mainboard etc...

Yes, I agree with you, as I also live in a high humidity area that would make an attack by crazy green moss from space (like the Creepshow movie episode) seem far more likely. Alas, that one time the spark flew and, like Dr. Frankenstein (He's alive! He's alive!), my GF MCP Pro acquired a life of it's own! (And a pile of frequent flyer miles from flying back-and-forth several times to GF HQ on FedEx Airlines, until GF was kind enough to replace the unit with a new one at no cost! And yes, I did tell them it was not their fault). Oh, and no sparks ever since, just that one day. Maybe an EMP, or a solar flare, or it was just too dry, or a combination, I don't know, but I'm not getting caught again, so now I touch the grounding plate before simming and for all mods I unplug everything from the the PC, carry it to the kitchen and place it on the steel surface next to the sink (grounded due to contact with pipes).

The only thing which happens automatically is that I touch the case before I open it, of course... and even here I never had a spark or something.

Alas, as Noel pointed out, the PC electrics are completely isolated from the case so by definition you would never get a spark.Cheers,- jahman

[dazz 69]

Have you tried with no DIMMS at all? even with no CPU installed? The MOBO should then beep for sure if it's ok. Double check the speaker is ok tooYou can get a PSU tester for some 10$. Very useful little tool

[Noel 4,563]

Have you tried with no DIMMS at all? even with no CPU installed? The MOBO should then beep for sure if it's ok. Double check the speaker is ok tooYou can get a PSU tester for some 10$. Very useful little tool

Dazz, as mentioned, I had an identical new mainboard, same same no beep, so pretty unlikely it's the mainboard I have to think.

[dazz 69]

Dazz, as mentioned, I had an identical new mainboard, same same no beep, so pretty unlikely it's the mainboard I have to think.

Yeah, I know you said that, and if the CPU fan spins the board must be working to some extent, and if you tested two of them it's most likely not the mobo, but it should still beep.I just ordered one of these for me: http://cgi.ebay.es/ws/eBayISAPI.dll?ViewItem&item=250790608512&ssPageName=STRK:MEWNX:ITOnce you test the PSU, If the PSU is faulty, the board might not be getting the juice to even beep, I don't know. If the PSU is ok, it's probably the CPU but then the board should beep, that's why I suggested to make sure the beep speaker is plugged and working properly, and to remove everything (GPU, RAM sticks, CPU...)